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Home , 2017 Monte Carlo Rally, Cyril Despres, Eric Camilli, Formula Two, Group R, Hyundai i20 R5

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Special digital edition • July 2016 • www.racecar-engineering.com

World of rally E [email protected] CONTENTS

Contents 4 HYUNDAI 20 DANNY i20 under the spotlights Slip angles on gravel 12 2008 DKR 26 RALLY 2017 Dakar winner What’s that coming over the hill? 18 Produced by Andrew Cotton, Sam Collins, Lightweight Mike Breslin and Dave Oswald

RALLY 2016 DIGITAL SPECIAL 3 R5 -

4 RALLY 2016 DIGITAL SPECIAL he FIA’s car and component cost-capped R5 regulations define competition cars which may appear ostensibly similar to World Rally Cars, but these machines are in fact Tone tier down from the WRC top level. They do have a similar powertrain layout to the current WRCs, with Hy’ Five passive front and rear differentials and no centre diff Hyundai’s i20 R5 is the latest in in their four-wheel-drive system. They can also have a turbocharged engine up to 1620cc, but this must a string of customer sport rally be based on a manufacturer’s production engine – hence WRC-style ‘Global’ engines are not allowed. The cars to roll out of manufacturers’ turbocharger must also be from a production car, while just five forward gear ratios are allowed with one final workshops. But will it be able take drive ratio. Suspension must be MacPherson strut, and the fight to M-Sport and Skoda all four uprights must be identical. Beyond these headline points, the R5 regulations out on the stages? are actually quite complex, incorporating maximum prices for components and assemblies, aimed at By MARTIN SHARP producing a highest price of €180,000 for a new asphalt specification R5 car before tax and registration costs – although FIA Appendix J still allows for free options in the areas of , batteries and the like. The R5 category has proven itself in leaps and bounds since M-Sport’s Fiesta became the first R5 car to hit the stages in 2013. This was some six months before the – delayed, and troubled – arrivals of its first rivals: PSA’s Peugeot 208T16 R5 and Citroen DS R5, both of The in full flow during the which were developed by . Also, while Rally ERC round in June, where it ran as a course M-Sport was working flat-out three years ago to bring car. Like all R5 cars the i20 is powered by a its Fiesta R5 first to the rallying party, Skoda Motorsport 1.6-litre production based engine, it is four-wheel- had already begun its Fabia R5 project, too. drive, and is cost capped at 180,000 R5’s arrived R5 is now firmly established as the top formula for national, regional and WRC2 rallying. With the effective demise of Regional Rally Cars (essentially more stringently inlet-restricted WRC cars) WRC2 is now dominated by R5 cars, as are national and regional rally championships across the rallying world. The Fabia R5 was not homologated until April 2015, scoring its first fastest stage time on last year’s . This demonstrated the Czech team had not wasted the Fabia R5’s lengthy gestation and that rival R5 teams needed to up their game. M-Sport met the challenge head-on with much improved power, torque output and characteristics in the Fiesta R5 Evo (also seen on entry lists as R5+), and Peugeot Sport has planned upgrades to its pair of PSA R5 cars to close the gap to the top-running Skoda and M-Sport Ford. Now, in the latter part of this year, privateer and semi-privateer teams wishing to compete in R5 have another, fresh, alternative: ’s New Generation i20 is getting the R5 treatment. But this new Korea-derived R5 car, designed and developed out of Hyundai Motorsport’s base in Alzenau, Germany, will only be homologated when everything is right. ‘We are still in a phase of development and testing and we don’t really want to rush if the car is not ready, because its basic design is even more critical than a ,’ says Michel Nandan, Hyundai Motorsport team principal – referring here to the complex and restrictive nature of the R5 rules, as mentioned above. ‘This is because you have to get it right at the beginning. There’s not a lot of jokers, first; which is also not good for the customer, so we have to provide a

RALLY 2016 DIGITAL SPECIAL 5 R5 - HYUNDAI I20

Hyundai Motorsport has been allowed to use the roll cage and the bodyshell from the existing 2016 i20 World Rally Car for the R5, but the rest of the car is completely different from its WRC sister

car which is reliable enough, which has been by the Korean headquarters in the middle share the people and the departments. But tested on the different surfaces and different of last year, and established in September. it’s true that for some aspects, of course, conditions that people will use it in, and to The company recognised that R5 is a top you need more people; for example in the give all the base set-ups to the people,’ Nandan category in all national rally championships, customer department you need to have other says. ‘So we really don’t want to rush it too and concluded it is important for Hyundai to people dedicated. So, we use some of the much, but it’s planned to homologate this have cars fighting in championships all over people from, let’s say, the workshop or sub- car during the summer some time. We will the world. Nandan says: ‘It was a very good assembly or things like that, and then people decide, I think, really at the last minute when decision to be allowed to do such a car.’ are working together on WRC and R5. But it will be: if it will be, let’s say, in July or August then with some other aspects of the customer [this year], but the plan is like this. We’re still R2 me too department, and also all the R5 engineering continuing our process of development and As the customer department grows, its next support, there will be dedicated people only also durability tests and everything.’ project will be an R2 car, but currently the involved in this customer business. All top rally cars have to be right at newly formed group is establishing itself and ‘It’s a mix of everything, but it is done the beginning of their lives, of course, but concentrating wholeheartedly on the i20 R5. in a way to use the efficiency of Hyundai Nandan’s statement is prescient and rally In the early design stage of the second-tier Motorsport and the departments which are engineers involved in R5 agree generally i20 rally car Korean engineers were brought already in place, plus the equipment, in order that the design stage of an R5 is crucial, and in to assist, partly because of the implied and to – first to save a bit of money, of course – arguably more difficult, than that of a WRC. regulated requirement to incorporate more but also to be more efficient,’ Nandan says. ‘In fact, I have to tell you, that is true,’ says standard components in an R5 than in a Essentially, this means that once the R5 car is Nandan. ‘With the regulation we have at World Rally Car. And indeed, Hyundai homologated it becomes the responsibility of the moment it’s a car which we can name Motorsport engineers involved with the engineers in the customer department. as a compromise car. This type of car is a WRC programme also diverted their talents But, as an important manufacturer’s big compromise because you have to cope toward the R5 car. Because of the cost- motorsport wing, does that department have with the rules … And I have to say it’s not so conscious nature of the rules, negotiations to show a profit? ‘Of course. It’s a customer easy to make a competitive car with all the with suppliers had to become more intense, business, it has to show a bit of profit, yes. But compromises you have to make. So, I think necessitating an increased head count in the first it’s a car which is done for the image. So, it’s not an easy job,’ he adds. team’s purchasing department. we have not to lose money, this is true, but if Hyundai Motorsport’s R5 programme is the Nandan explains: ‘The aim of Hyundai we can make a bit of profit it’s better. And it first initiative to derive from its new Customer Motorsport was to use all the different has to be done in this way. But the first thing is Racing department, which was approved department structures we have in order to to deliver a good car; reliable, and which can be used easily by the customer,’ Nandan says. R5 regulations are quite complex, incorporating Just before press time the new customer department completed eight days testing of maximum prices for components and assemblies the sole R5 prototype in a fortnight, beginning

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Christopher Roberts studied BSc Motorsport Technology and is now working for M-Sport as ’s Engineer

Before coming to Brookes I completed a three-year diagnostic course with Citroen and an apprenticeship as a dealer mechanic. During this time I started to help a Euro Nascar team, unpaid, on my weekends. After completing the apprenticeship I joined Ramsport and did a year as a rally mechanic. I read an article about the new Engineering School and was taken on a tour of Wheatley Campus during an Open Day. The facilities were impressive and the level of post-graduates was high, with strong links to surrounding industry.

Brookes offered a well-balanced education with teaching staff who have a high level of ability and knowledge. During my studies I continued to work as a sub-contracting mechanic in Formula Palmer and FIA Christopher Roberts (R) briefing Eric Camilli . A major factor in landing my first engineering role was having a combination of industry experience and academic knowledge. I joined AF Corse as a Junior Race Engineer during my final year at Brookes and left after one year to join M-Sport, initially in the Customer Engineering Department, with the aim of having a more in-depth role than just the race weekends.

The best moments of my career to date have been: • competing for the FIA Formula Two championship in 2012 (we finished a close 2nd!). • working with Jake Dennis when he won the BRDC McLaren Autosport Young Driver Award in 2013. • winning the WRC2 and Middle East rally titles in 2015 with Nasser Al-Attiyah. • rallying is much more of an adventure than circuit-racing!

The most challenging moments so far have been stepping up to the works WRC () programme for 2016, running Eric Camilli, who is stepping up to World Championship level with very little experience. There are many more performance variables to consider compared to circuit racing! tde.bz/obumems The Department of Mechanical Engineering and Mathematical Sciences mixes industry connections and a history of teaching engineering. Choose one of our courses at BSc, BEng, MEng, MSc or PhD level, and we will start your journey to the top.

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Wheel arch space at the front is not free and must remain standard. This has caused Hyundai and the other R5 manufacturers problems with wheel travel at the front end of their rally cars

on tarmac near Turin, then moving directly and Korean market Genesis coupe, while effectively at a gamut of temperatures to Sardinia for two days on tarmac and three the engine in the current, very competitive, and altitudes and a over a wide variety of days on rough gravel. Test development on all i20 WRC is an all-new Global unit developed distances, so maintaining the correct surfaces continues while a second prototype is through collaboration between Hyundai temperatures is an absolute priority. under build, which Customer Racing manager Motorsport and French firm Pipo Moteurs. Here the R5 regs bring in more head- Andrea Adamo says will aid development The i20 R5 also gets the Genesis coupe- scratching for the designers. For cost reasons a toward a final specification. ‘In some areas we derived all-alloy unit; in R5 guise developed by WRC-style cooling package is outlawed by the are developing two designs at the same time, Pipo and stroked down to 1.6-litre. The team requirement that R5 cooling components must but with only one car. Having a second chassis is currently investigating several different emanate from a standard mass production will make that process easier. With one we can production turbochargers for its R5 engine car. Nandan: ‘This is another point which is concentrate on tarmac testing; with the other from different manufacturers. To reduce cost, not easy. So you have to find some good cars. on gravel, and increase the amount of testing many engine sensors are standard, and the Okay, it is open; you can choose from any in the final months before homologation.’ engine ECU is the Magneti-Marelli SRG unit brand or manufacturer, but it has to be a mass used on the 2015 i20 WRC. production radiator, intercooler and things WRC crossover While boost pressure in a WRC engine is like that. So, it’s not so easy to find something Hyundai is allowed to use the roll cage controlled by electronics, for R5 an FIA- that’s giving the right performance.’ and bodyshell from the existing 2016 New specified pop-off valve is required to maintain Generation i20 WRC for the R5: ‘It’s a way also pressure below the mandatory 2.5bar Arch enemy to save a bit of time and not to do double maximum. This is a problem for the engine Another design headache produced by the R5 work; for instance, body calculations and engineers, as Nandan explains: ‘It’s totally rules is that wheelarch space is not free, as it is things like that,’ says Nandan. ‘But all the rest different [to WRC] because the boost pressure for WRCs. This includes the rule that is completely different, and it can’t be similar is regulated by the pop-off valve. The pop-off pods must be standard, which causes because of the regulations,’ he stresses. is something mechanical and it’s very difficult problems for all R5 teams: ‘It is a problem, Nandan is the first to admit that the team’s to be very close to the limit. And when the and in this case it is at the front, because now 2015 WRC car, based on the previous level i20, pop-off opens the pressure’s gone, so it’s a bit headlamps are bigger and bigger and these was forced to be something of ‘an acceptable more difficult to regulate it – but okay, it’s the are taking up a lot of space in the wheelarch. compromise’, because of logistical and time same problem for everybody.’ But from the regulations you can’t do anything; constraints. Its Global Engine was based on The R5 engine is a high efficiency you just have to use the standard components the all-alloy turbo 2-litre unit from the US competition IC unit designed to operate and so it is limiting the bump travel a lot at the front. But I think everybody else has more or less the same problem,’ Nandan says. An FIA-specified pop-off valve is required to keep During early R5 developments, while M-Sport struggled with Fiesta headlamp pressure below the mandatory 2.5bar maximum pod-to-top-of-front-tyre clearances – which

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The car’s aero package is similar to that of the 2016 i20 WRC. Its architecture is also similar, with no centre differential, and mechanical limited slip diffs front and rear

ended up at 0.5mm on maximum bump frontal openings in the R5 rules. In essence Ogier – effectively excludes the Czech team – the implications of these rules on Skoda most changes are at the front. from running World Rally Cars. Motorsport’s slightly different headlamp fixing While the New Generation i20 WRC runs a As for M-Sport, managing director Malcolm bracket arrangement meant the team would 6-speed Sadev gearbox and diffs, for the R5’s Wilson is the first to admit that involvement in have to cease development of the Fabia R5. regulation 5-speed unit Hyundai Motorsport the WRC is crucial to keeping his burgeoning The FIA then allowed modifications to the has opted for Ricardo assemblies. Apart from business alive. From 1997 M-Sport very brackets, enabling the Fabia development to the number of ratios the R5 transmission successfully ran Ford’s official WRC team. Then continue. But in the case of the i20 R5 those architecture is similar to WRC; no centre diff the Blue Oval pulled the funding from the 2013 brackets don’t interfere; it’s just that the big and mechanical limited slip diffs front and rear, season. Wilson bit the bullet and funded World headlamp pods are in the way. Hence, like its with a rear axle disengage mechanism. Rally Championship campaigns, chomping rivals, the i20 R5 enjoys sufficient rear wheel The latter operates hydraulically in the even further into the projectile by capitalising travel, and suffers from not enough at the front. i20 R5, similarly to that in the WRC, but using on the then-new R5 regulations. There is less freedom in R5 engine different components. And, because only The Fiesta R5 eclipsed every rival; on placement compared to WRC, too, and the size positive preload changes are allowed in announcement date, and competitiveness of the i20’s ex-2-litre unit restricts its engine R5, axle differential adjustments are not as and reliability. Today, with the Fabia R5 now compartment position further. Nandan: ‘There widely variable as they are in WRC, where two out on stages, as the build list of Fiesta R5s is not a lot that you can do, but I think it’s more adjustments are allowed. The steering rack heads toward unprecedented and remarkable or less the same for everybody, depending on contains Hyundai components, quite possibly heights, approaching 200 units, it is hardly the engine they are using.’ from the Santa Fe model, which are assembled any surprise that M-Sport runs top Welsh The Hyundai R5 engine and its ancillaries, into an i20 R5 rack in-house. driving talent in an official including cooling package, is at least 15kg works M-Sport Fiesta R5 Evo. heavier than the WRC’s, and not as ideally Works involvement Just after netted a sited, which results in a front-biased weight The majority of R5 cars are run by private stunning first WRC rally victory for him and distribution compared to the WRC car. and semi-private teams, although Skoda the New Generation i20 WRC on this year’s The car’s aerodynamic package is more or Motorsport and M-Sport World Rally Team do Rally of Argentina, Nandan stressed his team’s less the same as that of the 2016 i20 WRC, the enter ‘works’ R5 cars in WRC2. Each team has emphasis on R5 is entirely in-line with the team capitalising on the results of the World different reasons for this. Skoda is a member intentions behind the economy second-tier Rally Car aero development work for the R5. of the group and VW Motorsport’s WRC2 R5 formula, and it’s not looking at a Cost considerations demand minor changes WRC involvement – with recent consecutive works effort. ‘As a manufacturer involved in involving the need not to change parts too World Rally Championship victories for both the World Rally Championship then R5 is a often, together with different sized regulation the VW Polo R WRC and VW driver Sebastien proper customer project and customer car,’ Nandan explained. ‘We will, of course, assist and support teams which want to have ‘You have to use standard components, so this a car, but we’ll never do a kind of official championship, not Hyundai Motorsport. is limiting the bump travel a lot at the front’ It’s not our spirit at all,’ he says.

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Samco_connected_A5_final.indd 1 26/10/2015 12:40 DAKAR – DKR16

Skin deep Peugeot’s 2016 Dakar winner is wider, longer, lighter and faster than its 2015 challenger – and yet, as Racecar discovered, underneath it’s essentially the same car By ANDREW COTTON

12 RALLY 2016 DIGITAL SPECIAL eugeot returned to rallying in 2015 maintains the two-door coupe concept, and the wheelbase and width by 20cm, you have to with its 2008 DKR that first featured under the skin the team actually stayed with its more or less redesign the car! That is not very in Racecar Engineering V24N12. It original concept throughout the car. difficult because it is a tubular chassis, but it is marked the brand’s return to top ‘The concept of the 2015 car was very good, very useful because, with the first experience, Plevel international motorsport for the first time it was one of the conclusions that we made we used the opportunity to redesign the parts since the cancellation of its Le Mans programme after the 2015 Dakar race,’ says Peugeot’s and make them lighter, make the car easier in 2012, and also offered a better return on technical director, Bruno Famin. ‘It is the to maintain. Then, the car is also significantly investment with rallies in all of its key markets, same engine, same gearbox, same rear- lighter, even though it is bigger on the ground.’ including South America and China. wheel-drive concept, big wheels, on modern The team also took the opportunity to The team opted for a two-wheel-drive suspension. After that, we just wanted to further reduce the front and rear overhangs, and concept which allowed it to use bigger wheels, a improve the car in all the possible ways. worked on the aero for the car too. The 2008 lower weight car, and run with more suspension ‘One of the main weak points of the DKR16 benefits from improved aerodynamics: travel, but on tough terrain the vehicle would previous car was the lack of lateral stability,’ the bonnet and roof-mounted air-intake have struggle for traction compared to its 4wd Famin continues. ‘One of the conclusions was been heavily revised in order to provide more competitors. Yet for the 2016 version, the team to increase the width of the car by 20cm to the balanced downforce between front and rear. stayed with the concept, and its faith was maximum allowed by the regulations, but you The new air scoop also ensures better airflow. rewarded with a well-deserved win. cannot do it just like that; you have to increase Other evolutions lie under its carbon skin. The 2016 car actually looks significantly the wheelbase by more or less the same value. The suspension has been redesigned to deal different to the 2015 car. It’s wider and longer Already, when you decide that, even if you are more effectively with the different and rough by 20cm to improve lateral stability, but it still with the same concept, when you increase terrains. It also benefits from better weight

“You can never say that you are completely ready for the Dakar, because you simply never know what it will throw at you, but certainly this time we were more ready”

RALLY 2016 DIGITAL SPECIAL 13 DAKAR – PEUGEOT 2008 DKR16

distribution, as well as magnesium one-piece wheels for the first time, matched to lighter tyres from . These replace the aluminium two- piece wheels from 2015, with the combination resulting in a significant weight saving. The new car had been steadily developed since the first version finished the in Buenos Aires in January 2015. Peugeot’s engineers went over their ‘Lion’ piece by piece, analysing what could be done better, with the help of its Dakar experts Stephane Peterhansel, and Cyril Despres. These improvements were gradually applied and assessed through a series of tests, culminating in a one-two finish for Peterhansel and Despres on the China Silk Road Rally, using an interim-specification car. This was essentially the 2015 model with a number of development components for 2016 added. ‘We tested and raced in China where we finished first and second without a single problem,’ says Famin. ‘The competition level was not as high as Dakar or Morocco, but it was very good to make special stages without any problems. What we validated there was the Modifying tubular chassis was a relatively simple affair as it is easier than working on carbon, but a redesign was required lightweight wheels with the magnesium rims, nonetheless. The car is also lighter than 2015 version as the team made uses of lessons learnt to redesign some parts monobloc [one-piece], and the new commercial tyres from Michelin. We also had a better engine in terms of driveability, even if it was not the final version. They were the key points.’ Low grunt The team worked hard on the development of the 3-litre V6 turbo-diesel, finding that it lacked torque at low revs, partly a result of running first gear ratios that were just too long. That meant poor driveability at low speeds, and so it made a series of improvements to the new car. ‘The gearbox is exactly the same, except the ratio,’ says Famin. ‘The engine has very little torque at low revs, and the first gear ratio was too long. The low revs performance of the car was very bad, especially when you go higher Front and rear overhangs were reduced even further but the main difference between the DKR16 and its predecessor is that and higher with altitude. We are better now; the it is wider and longer with a lower centre of gravity. The roof-mounted air-intake has been the subject of aero development engine improved a lot, especially at low revs. We worked a lot on driveability, not so much on power, and on the gears with the same aim.’ With budget in mind, the Peugeot team had to be careful with its engine development. From its days in the Intercontinental Le Mans Cup (ILMC) and at Le Mans, it knew that the air restrictor has only a limited effect on outright diesel engine performance compared to gasoline. However, Peugeot’s engine is almost entirely production-based, and so has a natural cut-off point in terms of development. ‘The base of the engine, the cylinder heads, blocks pistons, con rods is all standard,’ says Famin. ‘It is a standard engine. Then you have to limit yourself in terms of turbo pressure if you want the pistons to survive. Then the turbo pressure is limited not by rule, but by engine basis, and in our case it is strictly standard.’ Famin also says that the development has While 2015 (left) and 2016 cars are visually different the new DKR sticks with the underlying 2wd turbo-diesel philosophy been throughout the car: ‘There isn’t one big

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The DKR15+ raced to first and second in China but with limited opposition – yet this at least proved new parts for the 2016 DKR were reliable

change that we have made on our car; instead revs. We’ve almost got a ‘problem’ now of how it has been a series of small evolutions in to manage all that power most effectively, but different areas, which together we hope will this is a very nice problem to have.’ amount to an overall improvement. The areas Carlos Sainz put in many hours of we have concentrated on include bodywork and development work before the Dakar. As a result, aerodynamics – as a result of which the car looks he accumulated plenty of experience of the slightly different compared to last year – as well brand new challenger. The Spaniard said before as engine and suspension, which is all under the the big event: ‘It’s been good testing and the car skin. The tests we have carried out up to now, has been running really well. The potential of In a bid to get down to the minimum weight limit Peugeot opted for as well as our one-two finish in China, indicate the car is much, much bigger than it was at this one-piece magnesium wheels and lighter Michelin tyres; but 2008 that we are heading in the right direction. You time last year and reliability has been solid too. DKR16 is still above the limit despite these and other measures really cannot compare our state of preparation We’ve changed quite a lot in the car in many key [for Dakar 2016] to how it was for our first Dakar, areas, so really we can call this one a completely when everything was new to us. Of course, you new car compared to last year.’ The off-road programme can never say that you are completely ready The off-road programme continues to offer for the Dakar either, because you simply never better value for money for the brand than the continues to offer better know what it will throw at you, but certainly Le Mans programme, but the desire to return to this time we are more ready.’ endurance racing still burns bright at Peugeot value for money for the Famin was speaking in the run-up to Dakar Sport, which is keen to address what it sees as 2016, where one of the , in the hands unfinished business. But cost control measures brand than Le Mans of Peterhansel, emerged victorious, Peugeot’s must come into force before it can contemplate first win in the event since 1990. The car also a return to Le Mans, possibly when there is a performed well in the hands of team mates major chassis change in 2018 or new fuel rules Carlos Sainz and Sebastien Loeb. in 2020. In the meantime the 2017 Dakar car is Peterhansel has said of the 2008 DKR16: ‘You already on the drawing board and that is where can really feel the difference now that the car is the company’s priorities lie in the medium term, longer and wider, with a lower centre of gravity, hoping to build on its superb win this year, its because it’s a lot more stable so cornering first in the event for quarter of a century. speeds are faster. You can feel the difference in Famin will hope that the new car will not the engine as well: not only is it more powerful, have to be that different from 2016, further but you can also use all the power even at low validating the team’s radical concept.

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FA_210X297_EU_CRP_2016.indd 1 4/13/16 10:46 AM WRC R-GT – ABARTH 124 RALLYE Little wonder For those looking for rear-wheel-drive thrills in the WRC, the R-GT class is just the ticket. Abarth’s diminutive 124 Rallye is the category’s first proper works-developed rally car By SAM COLLINS

here is a third top level in the WRC ‘What makes this car so different is that it is so that sits below World Rally Cars and close to the production car,’ Consalvo says. ‘If you R5, and for some years now it has look at the Polo WRC, it is beautiful engineering largely been overlooked. It officially but it is a totally different machine to the car Tfits under the regulations, but it is that is in the showroom. On our car we have a unlike anything else covered by those rules. It is double wishbone front and a five-link rear, and R-GT. Until now only a tiny number of cars have that is what you will find on the road car. We been built to the rules, some privateer also have a mechanical LSD, all in common and an abortive Exige variant from Lotus. But with the production car.’ then, at the Geneva Motor Show in early 2016, However, the mechanical components the 124 Abarth Rallye was revealed. themselves have little to do with the road Most in the media believed that this 124 going machine. The transmission is an off the was a mere concept car, or a show car. Those shelf longitudinal Sadev sequential unit and who did think it was the real deal believed it gearshifts are actuated pneumatically. Curiously, was designed to the R3 regulations, where it the road car and competition car transmissions The Fiat road car on which the Rallye is based would go toe-to-toe with the likes of the TMG have similar weights, according to Consalvo. comes with a soft top so Abarth needed to make built GT86. But Abarth is not doing its own hard top to meet FIA regulations. This things by half, and this is in fact the first serious Hot Abarth also helped increase the stiffness of the chassis manufacturer car built to the R-GT regulations. While the suspension has some general Maurizio Consalvo, Abarth technical commonality with the production car, such as development manager, says: ‘We want to use the inboard pickup points, it is also far from rear wheels has also impacted the layout of this car to go back to the roots of rallying, so that standard. ‘The dampers are bespoke four-way components in the car. ‘The road car and rally is our mission. We are launching a rear-wheel- adjustable units, we can make the travel longer car have almost identical weight distribution, drive car into an all-wheel-drive or front-wheel- or shorter depending on if you are on asphalt because on the competition car we have drive world. But for the enthusiast an AWD or or gravel. We worked on the kinematics a bit increased the weight a bit, the big engine fwd car is not the ultimate in terms of spectacle, but the pick up points are the same so that moves weight forward and the cage is heavy, its all about rwd. Its an emotional engagement was a bit limited,’ Consalvo explains. ‘When you but we save a lot of weight too in other areas, and we are emotionally engaged.’ only have only two driven wheels you need to Consalvo says. ‘We have got the engine behind The new Abarth 124 rally car is disarmingly get the best traction you can, and that was the the front axle and also, because this car will small, especially when the potency of the philosophy of the design.’ do some very long stages and events on the engine is considered, and it’s telling that Ensuring the best traction possible was WRC, we decided to find the extra space in the Consalvo speaks of the engine first. ‘The engine also the core aim of the chassis development, rear of the car to fit two full size spare wheels, is the most important aspect of the car. We have which is notable because the production car is rather than the usual one. This also helps us with installed the turbocharged DOHC 1.8 direct a soft top. ‘The hard top on the car is specifically the weight distribution a bit too, as it moves it injection 4-cylinder, we call it the Bialbero. It designed for the rally car. It is a composite rearwards a bit, which aids traction.’ produces around 300bhp depending on the construction and bonded to the roll cage to The cockpit of the car is surprisingly large, settings chosen by the driver [via a steering further increase stiffness. In fact the cage is not with a lot of effort clearly placed on making the wheel mounted control]. It is the same engine only designed to meet the FIA regulations but it 124 as usable as possible, and this has resulted architecture used on the Alfa Romeo 4C, but we is also meant to improve the torsional stiffness, in the use of an advanced electronic system. tuned it for the best output in competition.’ and as such it is linked to the front and rear Abarth has clearly outsourced this work but The production car has both the mild Fiat suspension turrets. The result of the cage and declined to declare who its partner is. ‘The variant and a more highly tuned Abarth version, the roof is an increase of 30 per cent in terms of interior ergonomics were important, so every and in developing the new rally car the Italian torsional rigidity,’ says Consalvo. single detail was analysed and adapted so the engineers wanted to keep things close to home. Working to improve the traction from the steering wheel is more complex perhaps than

18 RALLY 2016 DIGITAL SPECIAL The new Abarth 124 rally car is disarmingly small, especially when the potency of the engine is considered

some others, with controls for TC mapping,’ Consalvo says. ‘We have a TFT [flat screen] display on the logger and dash. It’s a next generation racing system, we used it not only to improve functionality but also to reduce weight. With this system you can make the adjustments on the car much faster.’ From the car’s development, and especially the layout of the cockpit, it is clear that the new Abarth R-GT is not a car for a works assault of the World Rally Championship, but for privateers to use to try to upset the big boys. ‘This is not a car for works teams, this is a car for normal people who want to go rallying at the top level. The turbocharged DOHC 1.8 direct injection 4-cylinder powerplant is called the Bialbero. It produces around 300bhp and it is We will go testing with it in September, and actually the same engine architecture as used in the Alfa Romeo 4C. Abarth has tuned the unit for World Rally competition we will be ready for the Rally in 2017. Our aim is to challenge the R5 cars, but privately developed 997, was hit with a be given a more generous restrictor and depending on the restrictor we have there is very small restrictor shortly before its debut on would be allowed to compete for overall the potential to take on the WRC cars in some Rally Germany in 2014. Many felt that this was wins. There are rumours that the Fiat Abarth conditions,’ Consalvo says. because the car was not works endorsed and will not be alone in the R-GT class in 2017, and Manufacturers using R-GT cars cannot score that it would be a bad thing for a privately built it may be joined by a new car from Alpine. WRC points but the crews behind the wheel and run car to mix it up at the front. Whether this leads to a more exciting, breed can, and they can compete for overall wins. However, there is still the belief that if a of rally car will only be clear on the Monte The last serious R-GT effort, Francis Tuthill’s works-backed car arrived in R-GT then it would Carlo Rally early next year.

RALLY 2016 DIGITAL SPECIAL 19 TECHNOLOGY – WRC SIMULATION Slide rules Add dirt and ice to the equation and the race maths gets a whole lot trickier – Racecar’s numbers man grapples with the slippery subject of rally simulation By DANNY NOWLAN

or the last few months my work has been dominated by a project to adapt ChassisSim for WRC. The tarmac bit was easy, but the tough bit has been Fadapting it to run on dirt and ice. It has been challenging, yet also incredibly informative at the same time. The challenging aspect has been resolving why you have to run well into the post- stalled region of the tyre, and then resolving how to stay there. But let me state from off; I am not pretending to be an expert on this. If truth be told, I’m actually writing this more for me than you at this point, so I can start to get some things straight in my head. That being said I’ve learnt a lot so far, so if you are involved with rallying or have any interest as to what happens when a car Figure 1: Lateral force vs slip angle characteristic for road tyre. Note how curve drops away once peak slip angle is exceeded goes sideways, then please read on. So here is the question: why do you want to go sideways in a rally car? For all of us that have been involved in circuit racing this is a cardinal sin. It looks impressive, but when it comes to tarmac racing we all know it’s a guaranteed way to kill your speed. The answer to this question lies in what the tyre is doing. Slip angles Specifically, the answer as to why we want to go sideways on dirt and ice comes down to the slip characteristics of the tyres. To really hammer home the point let’s illustrate this graphically – a typical force vs slip angle characteristic for a road racing tyre is shown in Figure 1. The thing to note in this curve is how significantly the grip drops away after you have exceeded the peak slip angle. In the post stalled region this is in the order of 10 to 20 per cent. Consequently, if you want to go fast on a road racing tyre there is no point being sideways, Figure 2: The force vs slip angle characteristics of a rally tyre – this shows there is grip to be had in the post-stalled region because the grip simply isn’t there. When you are on dirt and ice the tyre If you want to go fast on a road racing characteristics are a totally different ball game. When I was doing my research I came across two excellent thesis. These were Michael tyre there is no point in being sideways, Croft-White’s thesis from Cranfield University, Measurement and Analysis of Rally Car Dynamics because the grip isn’t there at High Attitude Angles, and a thesis from Stanford University entitled Dynamics and Control of Drifting in Automobiles by Rami Yusef Hindiyeh. The upshot from both of these is

20 RALLY 2016 DIGITAL SPECIAL that when you are post-stalled the grip doesn’t drop off that much. White did some basic tyre modelling from a beta sensor he had developed. This is presented in Figure 2. The key thing to note is what is happening in the post-stalled region. Looking at slip angles well in excess of 20-degrees the grip has only dropped of by 10 Slide rules per cent. This is significant, because it shows there is grip to be had in the post-stalled region. If the drop in post-slip grip is mild the reason there is grip is because of what happens with the longitudinal forces of the tyre at large slip angles. This is illustrated in Figure 3 along with the equations of motion with the car. The symbols in Figure 3 are:

Fy1 to F y4 – Lateral forces of tyres 1 to 4 respectively.

Fx1 to F x4 – Longitudinal forces of tyres 1 to 4 respectively

α1 to α4 – Slip angles of tyres 1 to 4 respectively. δ –Steer angle of the front wheels (equal steer Figure 3: Free body diagram of the forces acting on the racecar showing longitudinal forces of tyre at large slip angles angles are used on both sides to keep the representation simple). FYF – Lateral force applied at the front axle. EQUATIONS FYR – Lateral force applied at the rear axle. The tyre loads are applied vertically EQUATION 1 EQUATION 2 downwards for each tyre. All tyre forces are applied along the slip angle line. FXF and FXR are the sum of all the longitudinal forces at the front and rear EQUATION 3 EQUATION 4 respectively. Longitudinally this will not have a huge impact. But as we’ll see shortly it has big ramifications laterally. This is particularly apparent at large slip angles. EQUATION 5 EQUATION 6 Sine language But a note about small angle assumptions here. Strictly speaking they only apply to about +/- 10 degrees. However for practical calculation where; purposes we can stretch this to about 20 Vy sideways velocity. degrees. Let me illustrate what I mean. In radians Vx forward velocity. 20-degree is 0.349. The sine of 20-degree is r yaw rate. 0.342. The cosine of 20-degree is 0.94. Yes, we sacrifice a little bit of accuracy longitudinally but the sine of the angles are still very close. EQUATION 7 Consequently, the equations we are about to present still work out. The other option is to include the sine and cosine terms. While it is fully accurate, the problem is you start to lose any EQUATION 8 perspective on what the maths is telling you. Also, in rallying, it is rare to see a side slip greater +αα 21 ⎛ +αα 43 ⎞ than 30 degrees. While this is not ideal we are ʹ xyt )( YF FFrVVm YR (δ +++=+ )⋅ FXF + ⎜ ⎟⋅ FXR certainly not in fantasy land. 2 ⎝ 2 ⎠ Also, to simplify things we have lumped in the lateral forces here as well. Using small EQUATION 9 angle assumptions Equations 1 and 2 may ⎛ +αα 21 ⎞ ⎛ +αα 43 ⎞ be concluded. From the derivation presented z ⋅ ʹ = ⋅ (FarI YF ⎜δ ++ ⎟ XF ⋅−⋅ () FbF YF + ⎜ ⎟ ⋅ FXR ) in Wong3 (see references) the slip angles are ⎝ 2 ⎠ ⎝ 2 ⎠ Here, Equations 3 to 6. Resolving forces and moments mt = Total mass of the car. from Figure 1, the differential equations of the Iz = the rotational inertia of the car racecar become Equations 7,8 and 9. Equations 3 to 9 describe everything about how the racecar will behave. The thing to note here is the longitudinal forces. To reiterate they are applied on the slip angle line of the tyre. At this point you might be thinking, so what? But RALLY 2016 DIGITAL SPECIAL 21 TECHNOLOGY – WRC SIMULATION

the key lies in the lateral components of the Table 1– Rally car parameters Table 2 - Numbers for the balanced longitudinal forces in tarmac and dirt mode longitudinal forces – see Equation 10. Here Parameter Value FYF_FXF is the lateral force at the front Mode FXT (kgf) Lateral component (kgf) Car mass 1300kg induced by the front longitudinal forces Cornering g 1 Tarmac 198kgf 20.7 and FYR_FXR is the lateral force induced Peak slip angle: tarmac 60 Dirt 424kgf 118.7 by the rear longitudinal forces. Peak slip angle: dirt 160 Where things get really interesting is with CdA 1.1 what happens when the slip angles go up. Let’s Cornering speed 108km/h illustrate this with some numbers. Let’s consider a typical all-wheel-drive rally car that weighs EQUATIONS in at 1300kg. Some performance numbers are illustrated in Table 1. I realise the cornering g on dirt will be less than tarmac, but let’s keep these EQUATION 10 EQUATION 11 the same for the time being. I want you to get a feel for the magnitude of the numbers. + αα 21 1 2 FYF _ FXF (δ += ) ⋅ FXF FXT = ρ ⋅⋅ D +α ⋅⋅ amACV ytp So, balancing the speeds and assuming front 2 2 and rear slip angles to be the same we have Here we have, ⎛ + αα 43 ⎞ Equation 11. I know this is not strictly accurate FYR _ FXR = ⎜ ⎟ ⋅ FXR Fxt = Total longitudinal force applied (N) but it is in the ballpark and, as I’ve said, I’m ⎝ 2 ⎠ p = air density (kg/m3) doing this so you get a feel for it. Crunching the V = Car speed (m/s) numbers for the tarmac and dirt modes you get ap = Peak slip angle in radians the results presented in Table 2. mt = total car mass 2 ay = Lateral acceleration in m/s Engine force So, in tarmac mode we have about 20.7kgf of lateral force produced by the applied longitudinal force. In dirt mode this jumps to Figure 4: Here two 118.7 kgf. While the analysis is incredibly tyre forces are acting over-simplified it rams home the rally both laterally and observation that on dirt the engine force is longitudinally a significant part of your corner grip. But how do we determine that this is viable or not? We will enter what I will term the drift feasibility equation. Let’s illustrate this situation graphically – this is shown in Figure 4. As can be seen here we have two equal forces acting laterally and longitudinally. I will term this force R(α). Both of these components will have lateral components. Let me set R(α) out in Equation 12. Here C(a) is the normalised slip curve and FmOUT and FmIN are the outer and inner traction circle radius values. Our goal here is to find the best compromise of slip angle that produces the optimum lateral grip. Our total lateral forces will be given in Equation 13. Just to be clear, I am slaving the force R(α) to the force vs slip angle equation that we all know and love. However, I’m still keeping it in traction circle limits so that we don’t enter fantasy land. So the optimum slip angle will be given by deriving Equation 14 as a function of slip angle; using the product differential rule it is found that the optimum slip angle that will produce the most lateral grip will be given by this equation. Equation 14 is the drift feasibility equation. This won’t necessarily tell you the optimum slip angle you need to be at for drifting. However, it will tell you if your tyre can actually do it. As a case in point consider Figure 5a which is a road course tyre and Figure 5b which is a rally tyre. Evaluating Equation 14 for both of these curves show that figure 5a has an optimum slip angle of 6.2 degrees and figure 5b has an optimum slip angle of 16 degrees. Try doing this Figure 5a: Road course tyre. Equation 14 shows us that this tyre has an optimum slip angle of 6.2 degrees numerically. List out R(α) and the subsequent

22 RALLY 2016 DIGITAL SPECIAL Now we need to nail down at what angle we have to go sideways at derivatives. If you try and do it analytically you’ll yields the relation for the rear slip angle we are check Equation 17 and if all this adds up drive yourself nuts. This is the first step in seeing after, as seen in Equation 20. you have equilibrium. When this all checks if it is worth your while to go sideways or not. The solution of Equation 20 will give you out you have determined the rear slip angle So now that we have established if it’s viable a reference check. You are then going to go and side slip angle you should be drifting at. or not to go sideways we know need to nail through an iterative process to see if this makes What all these equations tell you is that down at what angle we have to go sideways. sense. In particular, if it is achievable through the drifting to improve vehicle grip is only viable Remember we are drifting on dirt and ice not slip angle curves you have. in low grip situations. just because it looks impressive but we are The other thing to check is the load transfer, Let’s re-inspect equation Equation 17, but doing this to get grip. The answer lies in the so that you have the traction. The limitation this time let’s do it through the lens of load lateral grip front and rear. will be the inside rear tyre loads. You will then transfer. As a rough rule of thumb your tyre loads Front to rear Let’s put some maths to this. To simplify things a little bit let’s use the bicycle equations of motion for the front and rear slip angles. This is presented in Equation 15. Here αf and αR are the front and rear slip angles. The front and rear lateral forces taking into account both the forces due to slip angle of the tyre and the longitudinal forces are shown in Equation 16. Let’s nail down the nomenclature here: CF(a) – Normalised force slip angle curve at the front CR(a) – Normalised force slip angle curve at the Rear Fm1 – Traction circle radius at the Left front tyre for a given load. Fm2 – Traction circle radius at the Left front tyre for a given load. Fm3 – Traction circle radius at the Left front tyre for a given load. Fm4 – Traction circle radius at the Left front tyre for a given load. Figure 5b: This time it’s a rally tyre. With Equation 14 we can see this has an optimum slip angle of 16 degrees Where things get really interesting is taking the derivative with respect to slip angle of Equation16. Then we see Equation 17. EQUATIONS In order to be worth your while to drift, the differential of the front and rear force curves EQUATION 12 EQUATION 13 must be greater than zero. This is where the grip ()()(= CR αα ⋅ OUT + FmFm IN ) FYT = .0 707 R()()()⋅⋅ (cos + sin ααα ) is and the reason the grip is there is as the slip angle increases you will actually be producing EQUATION 14 force you can use. It’s the reason that you see ∂Fy ∂R Sprint cars on an oval hanging the tail out 0 == R()()()(cos −⋅ sin ααα )+ ⋅(cos()()+ sin αα ) because that is where the grip is. If your car is ∂α ∂α rear-wheel-drive, the last bit of Equation 17 applies. If your car is front-wheel-drive the first EQUATION 15 EQUATION 16 bit of it applies. If you are all-wheel-drive then ⋅ +Vra = CF ()()()α ⋅ FmFm +++ αδ ⋅ F both come into play. For rallying, Equation 17 α = δ − y YF F 1 2 XFF outlines the appeal of all-wheel-drive cars. F Vx ⎛ ⋅ +Vra y ⎞ So what is the procedure to determine the = C ()()α ⋅ FmFm ++ ⎜2 ⋅α + ⎟ ⋅ F F 1 2 ⎜ F V ⎟ XF slip angle that you should be drifting to satisfy ⋅ +Vra y ⎝ x ⎠ Equation 17? You start by choosing a corner αδ F += V YR = CF R ()()()α ⋅ 3 FmFm 4 ++ α ⋅ FXRR speed and looking at the peak curvature you x want to corner at. You then nominate the factor −⋅ Vrb α = y of grip you want to maintain at the rear. The crux R EQUATION 17 of this is that we want to maintain equilibrium Vx ∂()YF ∂ CF (α FF )() both laterally and longitudinally. = ⋅ ()1 FmFm 2 ++ 2 ⋅ FXF Keeping the slip angles the same front and ∂α F ∂α rear we have Equations 18 and 19. Here tspR ∂ F is the torque split at the rear and FXFR is the ()YR = C ()()α RR ⋅ 3 FmFm 4 ++ FXR factor of rear longitudinal tyre force we want to ∂α R contribute to the lateral grip. Putting 18 into 19

RALLY 2016 DIGITAL SPECIAL 23

TECHNOLOGY – WRC SIMULATION

for a given aero load and load transfer are given EQUATIONS in Equation 21. Where the downforce is not significant what will limit you will be the inside EQUATION 18 front and rear tyres unloading. Consequently 2 your ability to apply the longitudinal forces you α R ⋅ XR = FF XFR wdr Vm Xt ⋅⋅⋅⋅ iR need, to ensure Equation 17 is greater than or equal to zero, will be limited. Strictly speaking EQUATION 19 you could channel all the longitudinal force to the outside rear wheel, but you will have a ⎛ 1 2 2 ⎞ destabilising moment due to the tractive force FXR = tsp R ⎜ ρ ⋅⋅⋅⋅ D + α VmACV XtR ⋅⋅ iR⎟ ⎝ 2 ⎠ trying to destabilise the car.

EQUATION 20 The drift zone The last topic to touch upon is; what does 5.0 ρ ⋅⋅ AC F α 2 + D α −⋅ XFR = 0 the racecar stability look like in the post- R m ⋅iR R tsp stalled drift zone? As discussed in some of my t R previous articles, there is an excellent tool to EQUATION 21 look at this, which is the stability index. This can be written as Equation 22. 1 2 awf L ρ ⋅⋅⋅⋅⋅ VAC prr ⋅⋅⋅ ham Inspecting Equation 17 and putting it into wdf t ⋅⋅ gm 2 yt TL1 = + + Equation 22 we will still have some measure 2 2 tm of stability. However, it will be much more 1 2 marginal. This is because the slope of the force wdf ⋅⋅ gm awf L ρ ⋅⋅⋅⋅⋅ VAC prr ⋅⋅⋅ ham TL = t + 2 − yt vs slip angle curves are much smaller. The 2 2 2 tm applied longitudinal forces are the dominant terms. The combination of Equations 17 and 22 1 2 awr L ρ ⋅⋅⋅⋅⋅ VAC 1 prr ⋅⋅⋅− ham mean that if you are sliding in a rear-wheel-drive wdr t ⋅⋅ gm 2 () yt TL3 = + + car you have no option but to keep the power 2 2 tm applied. This was also confirmed in Hindiyeh2, 1 2 where the engine force is used as an integral wdr ⋅⋅ gm awr L ρ ⋅⋅⋅⋅⋅ VAC ()1 prr yt ⋅⋅⋅− ham t 2 part of his drift controller. TL4 = + − 2 2 tm Lastly, to show this isn’t just theory, the beginnings of it have now been incorporated EQUATION 22 into ChassisSim, as you can see in the example ∂F ∂F ⎛ ∂F ∂F ⎞ r of a predictive rally simulation done in real time a ⋅ YF b ⋅− YR ⎜a 2 ⋅− YF + b 2 ⋅ YR ⎟ ⋅ controlling the car in the post-stalled zone of ∂ ∂αα ⎝ ∂α ∂α ⎠ VX the tyre, shown in Figure 6. SI = ⎛ ∂ ∂FF ⎞ The first trace is speed, the second is steered ⎜ YF + YR ⎟ ⋅ wb angle, and the third trace is throttle. However, ⎝ ∂ ∂αα ⎠ the real traces are the fourth and fifth traces that show front and rear slip angles. The stall angle for this tyre is six degrees. The front slip angles are in the order of four to five degrees. However, you can see the rear slip angles are in the order of 10 degrees and they are being controlled. I should add that the car model needs work. In closing, the vehicle dynamics of drifting are an exceptionally interesting field. The thing that dictates why you want to drift is what happens to the tyres on dirt and ice. Here the slip angle curves drop of moderately in the post-stalled region of the tyre. This makes it viable to slide and we can readily calculate where we need to be drifting. While this is certainly not the last word on the vehicle dynamics of rallying, I trust what I have given you is the mathematical framework to put some numbers to it. Figure 6: Some predictive rally action from ChassisSim which shows the car being controlled in the post-stalled drift zone References 1) Measurement and Analysis of Rally Car Dynamics at High Attitude Angles, Michael Croft-White, Cranfield 2005. 2) Dynamics and Control of Drifting in Automobiles, If you’re sliding in a rear-wheel-drive car here, Rami Yusef Hindiyeh, Stanford University 2013. 3) Theory of Ground Vehicles, JY Wong Wiley you have no option but to keep the power applied and sons, 1978

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Contact us about exhibiting today gg +44 (0)20 8843 8800 or visit www.advancedengineeringuk.com WRC – 2017 CONTENDERS The stage is set A new breed of quicker and more spectacular World Rally Cars will be unleashed next season. But where do the manufacturer teams currently stand in the 2017 development race? Racecar investigates By MARTIN SHARP

The extended body width of the next generation 2017 WRCs provides increased space to enhance side impact protection for crews

ere are the headline fi gures designs and development components for its more freedom we have for suspension pick-up concerning next year’s new WRC 2017 World Rally Car. Its fi rst test was in Finland points. That was the purpose of most of the tests regulations. Close to 50bhp more last August, just one month after the new we did last year with so many diff erent specs, power than this year (to 380bhp), rules were approved. Given the time scale it is but last year it was not really a 2017 car.’ Hfrom a turbo inlet restrictor diameter increase impressive that the test car appeared with wider from 33mm to 36mm for the 1.6-litre 4-cylinder versions of the 2015/16 wheel-arch extensions, VW’s early start engines. Minimum car weight goes down by development wider track suspension, and Such continuously honed specifi cations enabled 25kg, and handling and traction improvements an intermediate, active centre diff -equipped Demaison to consider it prudent to sign off the come from a central diff erential with active transmission solution. By this year’s Rally fi nal car spec by mid-2016. ‘In October we have slip-limiting. The cars will also be 55mm wider. Portugal the team had completed ‘more than to give a fi nal document, but we want to start Meanwhile, aero changes include increased 5000km, less than 10,000km,’ of testing, says VW in January with three cars at Monte Carlo. So, if dimensions for the fi xed rear wing, with an Motorsport’s chief chassis engineer Francois- we have three cars then we have [to have] the extra 30mm overhang allowed. A 60mm front Xavier ‘FX’ Demaison, rather enigmatically. spares, and we have also three overhang is also permitted, and the rear diff user ‘Because of the more open rules for the weeks later. If we have bad luck in Monte Carlo design is free, within maximum dimensions. suspension and geometry we tested diff erent and we crash three cars, we need also spare These new rules were approved by the FIA options,’ Demaison says. ‘The best compromises; chassis’ ready for Sweden. WMSC on July 12 last year and Volkswagen the best way to increase the track width and ‘We are in the validation phase for the Motorsport was the fi rst top team to test the maximum potential we could get out of the transmission, for the suspension, for the

26 RALLY 2016 DIGITAL SPECIAL Citroen has taken a sabbatical from the WRC this year to concentrate on the development of its 2017 car. The aero on the new C3 rally car has benefited from the company’s WTCC experience

Because the Yaris WRC will be freshly homologated as a World Rally Car for 2017, the rules allow Toyota to have an unlimited testing programme in the run-up to its top level rallying comeback

The current spec Fiesta WRC. M-Sport is testing many of the components for the 2017 Ford on a 2016 car, which it says has a very similar chassis and suspension geometry to the new Fiesta

bodyshell, the cooling, everything. The only campaign, and meetings between the FIA and yes or no; this we can’t do, this we can do, and thing which is not tested yet on the car is all of teams have made some progress, but before a have a final decision,’ Demaison adds. the bodywork,’ Demaison adds. final ruling the requirements of each car model Currently the FIA has suggested mandating This is because, at the time of writing, the need to be taken into account. a further 30 litres of deformable foam in each manufacturer teams and the FIA were discussing front side door to the existing 60 litres. This the side impact protection of the new cars. The Foam call is still yet to be ratified by the FIA WMSC, but tragic death of co-driver Michael ‘Beef’ Park after Demaison says: ‘For sure, we increase the car by will likely include the possibility to increase Markko Martin’s WRC hit a tree 55mm compared to today, so it’s 27.5mm per door thickness for those cars which cannot sideways in the Margam Park stage on the 2005 side, so yes there is room. It’s always a fight with accommodate 90 litres of foam in each side Wales Rally GB convinced the FIA to mandate designers in the road car department; they do door. It is, however, possible that further side specific deformable impact-absorbing foam in not want us to change the shape too much, but impact protection provisions will also ensue. driver and co-driver side doors. But at the time for safety reasons we will do it. Active differentials were part of the old 2-litre the doors remained standard thickness, so there ‘We’re talking with the FIA, just to find turbo World Rally Car designs. Then the 1600cc was limited space for the foam. a solution which – because all the cars are turbo regulations demanded passive front and The extended body width of the next different – gives all cars the same level of rear axle diffs and no centre differential. Under generation 2017 WRCs provides increased safety and protection. That’s the most difficult the 2017 rules the passive axle units remain, but space to enhance side impact protection thing. So that’s why we do it together; all the an active centre differential is again allowed. for crews. It is a manufacturer team-driven manufacturers. We can check on our car and say Demaison explains why: ‘We mainly pushed

RALLY 2016 DIGITAL SPECIAL 27 WRC – 2017 CONTENDERS

transmission during the week after Rally Portugal, and planned to test this a week later, after rig testing had proven gearbox and differential components. Its 2017 tests began in April, using a 2016 five-door i20 WRC, as Hyundai Motorsport team principal Michel Nandan explains: ‘We have dedicated one car to do all this; a ‘mule’ car in order to test some components and not wait until the 2017 bodyshell; not to lose too much time.’ Hyundai’s progress Engine components, a bigger restrictor, and new coolers have already been tested in this way by Hyundai. The 2017 wider track suspension is designed but yet to be tested, but it plans to build a full 2017 specification car ready for testing around July time, 2016. That 2017 specification Hyundai WRC will be the three-door coupe version which the team originally planned to be its 2016 challenger. It started testing with it, then realised production figures for the 25,000 minimum required for the model would be marginal for 2016. So Hyundai Motorsport opted for the five-door i20 as the base for is 2016 WRC challenger. But the manufacturer has now hit the Citroen has experience with the Global Race Engine (pictured) it will use in the WRC from its programme in the WTCC, three-door coupe production targets for the where it also runs with a 36mm inlet restrictor as per 2017 WRC regulations. Power goes up by 50bhp to 380bhp next year 2017 WRC homologation and Nandan is happy that the lower drag characteristics deriving for this because it’s for us like having a proper it’s not his job; we need really good technical from the smaller frontal area of this model damper in the drivetrain, which causes much feedback from him,’ explains Demaison. He says will have significant advantages. less technical issues with driveshafts, with the the same of early footage of Toyota’s 2017 WRC Nandan does have some reservations about propshaft, with the internal parts of the diffs. testing in Finland and Spain, with four-time WRC the new rules, though. ‘Yes, the cars will look a That’s the main thing, and we all agreed to have Champion Tommi Makinen behind the wheel. little bit more fancy, but for me the worst thing a very simple and basic active strategy.’ is the increase of power – I would not have This will likely contribute to making the Toyota’s advantage done it. The cars are quick enough now. I would more powerful and lighter 2017 cars somewhat Because the 2017 WRC will be have given them more torque [Maximum boost more controllable in corners. But will the cars freshly homologated as a World Rally Car the pressure is retained at 2.5bar absolute; therefore then look more as if they are cornering on rails? rules allow works team, Tommi Makinen/Gazoo torque output will be affected minimally] to There is internet video footage of some 2017 Racing to have no limit on the amount of have a bit more of a spectacular impression, but WRCs on test already, and this is Demaison’s pre-season testing allowed, and it is the same the power I would not have touched. I think it’s expert opinion: ‘The movies we have seen of the for Citroen Racing with its C3 WRC, which will too much – especially now that the rallies are ’17 cars on gravel, and even on tarmac, for me also be a new car to WRC homologation. This much faster than before, because all the stages, they look a bit more spectacular.’ freedom is not available to VW Motorsport, if you have a look, are a lot faster.’ But he also makes the point that early tests which will be homologating the same, Maximum allowed WRC hydraulic pressure are development exercises; not demonstrations victorious, three-door base Polo, as campaigned is now 120bar, and providing the required of ultimate pace. ’s three in previous seasons, as its 2017 WRC. pressure to operate the active centre differential WRC drivers have already tested the 2017 car Which is partly why the team started in the Hyundai’s 2017 transmission when specification, but the bulk of the test driving testing early, Demaison says: ‘We were limited fitted to the 2016 ‘mule’ i20 WRC has not been tasks are undertaken by twice World Rally in the number of days testing, so it’s quite a difficult, Nandan says. ‘[The hydraulic system] Champion Marcus Gronholm: ‘When we have disadvantage. We are were limited because it is quite similar to what we have here [in the Marcus testing, he is not driving at the same says in the rules that if you keep the same model 2016 car]. We have already a hydraulic block speed as [Sebastien] Ogier, Jari [-Matti Latvala] you have limited testing. We had 30 days for with two electro-valves for the gear change or Andreas [Mikkelsen]; it’s not what we’re both 2015 and 2016, so 15 and 15 for each year.’ and one for the rear [disengage] clutch; so now asking. He doesn’t need to push 100 per cent, But how far ahead of his rivals does [in 2017 spec] there is no rear clutch, but there Demaison consider VW to be? ‘This is really is a centre diff. It will be modified [to cater for difficult to say: are we ahead? We don’t know. greater hydraulic pressure], but it’s nothing. It’s Volkswagen’s first test We are doing the work we think is necessary to something we have already tested.’ be ready for Monte Carlo and we will judge in Before Rally Portugal the 2017 i20 WRC mule was in Finland last August, Monte Carlo. But before that it’s really difficult had already covered some 1000 test kilometres, to know [how we compare] with the red ones, adequate when considered simply as a vehicle just one month after the Citroen, with the experience they have.’ to test components. But has Nandan formed any Meanwhile, Hyundai Motorsport took opinion on rival 2017 WRCs? ‘I’ve had a look at new rules were approved delivery of its 2017 specification Sadev the videos. Yeah, okay, you can see things, but

28 RALLY 2016 DIGITAL SPECIAL for sure it is not the final specification; especially test car was under build at the time of writing. in bodywork, because the regulation is not Chassis, engine, transmission and aerodynamic ‘The potential of our final, there’s still the side impact devices to be developments will continue apace until defined. It could change a lots of things, but homologation for the 2017 : new World Rally Car yes it gives some ideas. It’s always interesting to ‘We’ve only just begun the journey,’ Fregosi says, have a look at what the others are doing. But I adding: ‘That point [homologation] seems so far is quite incredible’ think that for everybody that is now running away, and yet it’ll be here before we know it.’ the [2017] car, for sure it is not the same as their It’s a serious approach, then, from the French final spec will be,’ Nandan says. team, running the test 2017 C3 WRCs before the new C3 road cars hit showrooms, which is Citroen’s sabbatical expected in August. And it’s an approach that Another varied approach to the 2017 WRC is the M-Sport team would love to share. But the considered tactics of Citroen Racing, which currently this seems unlikely. is taking a sabbatical from the WRC this year, while PH Sport runs DS3 WRCs under the Abu Ford’s tight deadline Dhabi Total World Rally Team banner. This year is The Cumbria, UK-based M-Sport squad is also the last time Citroen will contest the World determined to be at the 2017 Monte Carlo Touring Car Championship, which leaves 2017 Rally with a new World Rally Car, although free for an all-out WRC onslaught. team insiders rate the timing as tight. Some The aggressive stance of the 2017 WRC cars is clear in this pic of Based on a yet to be launched new C3 road work on the new car has begun, with the main the VW Polo development car, but the bodies of the new cars might car, the WRC version had its first shakedown test developments due to commence in early June, yet look a little different as new safety regs have yet to be finalised in early April, driven by Alexandre Bengue on and M-Sport is expected to have the new the small tarmac track next to Citroen Racing’s mechanical components ready for testing in a Satory, Versailles site. The car was then tested on current Ford Fiesta WRC bodyshell in July. rocky gravel by Chris Meeke, and then by Craig A potential difficulty for the M-Sport team Breen, without major problems. After the tests, is that a totally different new Fiesta road car is and with a broad grin, Meeke said: ‘The potential imminent. The team does not have a physical of our new World Rally Car is incredible.’ example of the new road car yet, and there are Meeke then put more testing miles into two possible launch dates mooted, but none the C3 WRC in Portugal. Conditions were very decided. ‘It’s not a facelift; it’s a completely new mixed, with some rain, hail and fog joining the car,’ says M-Sport managing director Malcolm occasional sunshine. Component lifing was Wilson. ‘The wheelbase is about the same and part of these tests, together with performance we have the old [current] base to work on; that’s and crew comfort development. Citroen Racing how we can do it. Some of the things associated technical director Laurent Fregosi said: ‘We were with the new bodyshell will be different, but actually quite pleased to have these variable the actual geometry – all the CAD data of the conditions because they meant we could test chassis – is the same, which means we can different set-ups and assess how the bodywork basically modify the current car to the new car. stood up to being loaded with mud.’ I’m not concerned; the main thing is running the The team has worked on the 2017 WRC [new] mechanical components, which we will project for over a year now, from first design be doing from July onwards.’ Hyundai Motorsport head Michel Nandan says that enough three- stroke to built components, assemblies and There will be changes to the engine, too: door new Hyundai i20s have now been built for the road for it to be car. A current priority is to improve access to a different cylinder head, a different turbo, homologated, and the team will use it for its 2017 WRC base car components likely to be replaced in service. perhaps slightly different pistons, a modified oil One advantage for Citroen Racing is that pump, and much of the ancillary items, but the the Global engine in its C-Elisee WTCC racers is cylinder block and crankshaft will remain the similar to that chosen for its 2017 WRC, and it same as in M-Sport’s 2016 engine. The team’s has run with a 36mm diameter inlet restrictor Focus RS WRC had a Ricardo transmission and from the beginning. So the team has a good the same specialist is supplying the gearbox and working knowledge of the similarly restricted centre differential assembly, and front and rear engine in the 2017 World Rally Car. ‘The car diffs, for the 2017 Fiesta WRC. immediately possessed the same power level While Wilson confirms the arrival of the as we’ll see next year. We have also tested the all-new Fiesta road car will restrict when his latest suspension systems,’ Fregosi said. team can launch the 2017 WRC version, he is A further bonus of the WTCC racing still adamant that the car will be ready in time: programme is the team’s increased knowledge ‘The plan is to be in Monte Carlo. I’m not that and experience in aerodynamics, team director worried; we’ve enough experience in M-Sport. Yves Matton explains: ‘Before we had virtually We’ve just done a [Focus] rallycross car in six no real experience in aerodynamics. It is now a months from start to finish, that’s as quick as field in which we have genuine expertise.’ anything going straight out of the box, so I’m Adopting a just-in-time approach to account not that concerned,’ Wilson says. for long lead-time items, assembly of the first We will have to wait until Monte Carlo to prototype was completed in under a month. find out whether his confidence is justified. M-Sport boss Malcolm Wilson says he is not worried that the new Data analysis from the tests is under way to A great many other questions about WRC Fiesta on which its 2017 WRC car is to be based has not yet been hone the specification and a second, tarmac, 2017 will be answered there, too. launched and he is confident the new car will make Monte Carlo

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