Welcome to Revolution 5 Spring is in the air and the racing season is once again upon us. In this issue of Revolution we take a look at the exciting sport of truck racing – at 5500kg upwards, these must be the largest racing machines on the track, and 30 of them heading for a chicane make a magnificent spectacle! We’re also still following the progress of diesel sports from Audi and Peugeot as the Le Mans 24 hour race is on the horizon.

Garrett outlines why replacement of VNT™ units is preferable to repair; both Spin Doctor and Mark Dickinson’s column address the importance of oil to the ; and we look at a number of innovations on the engine front from a wide range of manufacturers.

New engines mean more demand for replacement and you can rest assured that BTN Turbo will help you with the units you need. As ever, we offer turbo recognition from the VIN, a ‘new for old’ replacement policy on an increasing number of units and our ‘12 month no quibble’ warranty on commercial vehicle turbos. For more information on our services, including fault finding, build sheets and our complete catalogue, please go to www.btnturbo.com.

Enjoy the spring and summer and remember, if you need any help or advice about turbochargers, just call BTN Turbo on 01895 4666666.

Rachel Birch Editor

VW 1.4 litre engine has a turbocharger and

The innovative TSI engine from Volkswagen provides maximum power with minimum fuel consumption, by using a turbocharger and a supercharger. Dubbed the ‘Twincharger’, it is a 1.4 litre that gives excellent power delivery throughout the speed range with no turbo lag; fuel economy of over 38mpg in a Golf GT; and an output of 168bhp. The manufacturer claims that it has all the benefits of a petrol engine in that it is quieter than a diesel and has a wider rev range, but it delivers comparable fuel efficiency and torque (177 lb ft).

The thinking is quite simple. In order to combine the power characteristics of a large engine with the lightness and economy of a small engine, a turbocharger is the obvious answer when the engine is running at high revs. However, low exhaust pressure at low revs is an inherent problem and can cause turbo lag. This is overcome by the use of a high speed, mechanically-driven compressor, or supercharger, controlled by an automatic charge pressure control system. It kicks in during initial acceleration and supplies additional boost by working alongside the turbo when additional power, such as when overtaking, is required.

FSI direct allows a high compression ration of 10:1 and the ability to pass 7000rpm without risk: in the Golf, that means a top speed of 137mph, 0-60 in 7.7 seconds and more than 38.2mpg, with a CO2 output of just 175g/km.

The TSI power plant, which won the Best New Engine Award in the International Engine of The Year Awards, is available in the Golf GT and Sport, and the Touran SE and Sport. Mark’s remarks Industry comment from Mark Dickinson, Sales & Marketing Director of BTN Turbo How drivers destroy their turbos

Looking at the Spin Doctor article on oil in this issue of spinning at up to 200,000 rpm, reaches a phenomenal Revolution, I was struck by the fact that many drivers temperature and things start to cook! The oil begins to ‘coke’, don’t know how to treat a turbo. producing particles that will grind their way through the turbo bearings tomorrow morning when he starts the cold The businessman, for example, sets off in the morning in his engine again. brand new turbocharged . Short on time, he has his foot to the floor before the oil has warmed and circulated properly. I suppose that we in the aftermarket should be grateful – it Then, after a couple of hours, he dives into the motorway means more business for us supplying and fitting the services, turns off the engine without letting it idle and goes for replacements. You can be sure that, when he is off the road, a ‘comfort break’. Little does he realise how much damage he is that businessman wants his car back quickly, which is why we inflicting on his turbocharger. As the oil stops circulating and hold massive stocks and can get you the replacement turbo you the comes to a halt the turbo, which seconds ago was need by next day delivery.

The turbocharged Saab that doesn’t need petrol or diesel

Saab gave green motoring a performance boost at the 2007 an incredible 300bhp. This has been possible through Geneva Motor Show when it unveiled its latest BioPower modifications to the engine management system and internal technology – the first production-based engine to be optimised components, allowing the use of greater boost pressure with a for pure bioethanol (E100) fuel. raised . This exceptionally high specific power output of 150bhp per litre demonstrates scope for future Bioethanol fuel is produced commercially from agricultural crops ‘rightsizing’ – using small, high output engines that also deliver such as wheat, corn, grain, sugar beet and sugar cane. Unlike energy savings. petrol, its consumption does not significantly raise atmospheric levels of CO2, which some scientific research suggests is a major Peak power is complemented by a substantial 400Nm of torque, contributor to global warming. This is because emissions released giving the engine similar power to a naturally-aspirated 4.0 litre during driving are balanced by the amount of CO2 that is unit. The Saab 9-5 BioPower 100 Concept accelerates from 0 – 62 removed from the atmosphere when crops for conversion mph in just 6.6 seconds and from 50 – 70 mph (in fifth gear) in are grown. an even more impressive 8.2 seconds.

Saab launched its BioPower flex-fuel technology 18 months ago and its entire range is now available with engines that can run on the eco-friendly yet potent fuel source bioethanol E85, standard unleaded petrol, or any mix of the two fuels. They enjoy substantially reduced fossil carbon dioxide (CO2) emissions, whilst delivering significant increases in power, when running on bioethanol E85 compared to when running on petrol.

BioPower 100 is an exciting evolution as it requires no fossil fuel at all, and it demonstrates the great performance potential of bioethanol. Combining Saab’s turbocharging expertise with the use of high-octane E100 fuel, the 2.0 litre 9-5 engine produces White Van Man: dragon or knight of the road?

Is the term ‘White Van Man’ affectionate or derogatory? 74% of van drivers think it’s the latter, or that it doesn’t apply to them personally, according to a survey carried out by GfK for Ford in March of this year. Indeed, 37% said it was ‘rude or insulting’ although 11% are proud to be called WVM.

The survey revealed that today’s definitive White Van Man is male, about 42 years old, married and wants to retire early. His favourite foods are curry and roast dinners and a significant number choose organic foods. His preferred drinks are beer (49%) and tea (11%) and he doesn’t smoke (62%). Speed limiters result in extremely close racing He reads The Sun (38%) and listens to local music stations (32%) and BBC Radio 2 (28%). His favourite sport is football - 79% watch and 37% play. 80% eat in the cab of their van with 26% using transport cafes. A Race of Giant

The winner of the very first truck race at Donington in the mid-80s arrived with a fully loaded trailer, unhooked it, competed, collected the silverware and on Monday morning was back on the road to deliver his load!

The sport has moved on a great deal in the past two decades and the When it comes to working, the top factors machines used nowadays are a far cry from their road-going cousins. in the job satisfaction stakes are providing client satisfaction and finishing jobs on Limited top speed time. He feels he is professional and wants to be perceived as such: 69% like to keep Just as in every form of motorsport, the main objective when their van clean and more than half do care preparing a racetruck is to make it go faster, but truck racing has about how other drivers see them. some regulations that make it equally important not to go too fast. Reassuringly, more than nine out of ten Due to the sheer size and weight of these speedy six-wheelers, a agree that people who drive while speaking maximum speed limit of 100mph was enforced right from the on the phone are dangerous. beginning of the sport, for safety reasons. And, although most vans are white (64%), One side-effect of this rule is that the racing tends to be extremely WVM can also be Blue Van Man (13%), Red Van Man (8%) or Silver Van Man (7%). close. No-one can run away into the distance purely because of a superior top speed. Of course, this places a premium on acceleration Keeping mobile is very important: WVM has and braking. a responsible attitude to van maintenance and 58% say that their van breaking down Quicker than a Porsche 911! is like losing their right arm. The 12-litre turbocharged diesel engines used by the majority of the With annual van sales in excess of 325,000 in the UK, there are plenty of vans out there field are tuned to produce in excess of 1000 horsepower, which is for us to maintain. Trust BTN Turbo to have more than double the output of even the most powerful road version. the unit you need, when you need it. Combined with the vast torque figure of over 3000Nm, this gives the Stuart Oliver’s water cooled brakes add to the spectacle nts:over 5500kg and over 1000bhp

racetrucks amazing straight line performance - from a rolling Safety first start, a racetruck can out-accelerate a Porsche 911 up to 100mph! The other vital modifications to any racetruck are those concerned In the early days, the main means of increasing engine performance with safety. The rules oblige all competitors to fit a full roll cage, was to tune the and increase airflow by installing an safety harness and racing seat. Fortunately this equipment is rarely enormous turbocharger, or two! Nowadays the engines are all tested as, despite their top-heavy appearance, racetrucks tend to electronically programmed: the turboboost effect coupled with carry their weight very low down and it’s very unusual to see one roll. overall engine performance is critical and teams optimise power Truck racing is a non-contact formula but, with up to 30 trucks on output by programming the engine management system. the track, bumps, scrapes and exchanges of paintwork are a regular part of the action and this physical aspect of the racing helps to Production chassis and cab attract enormous audiences. The regulations insist that the original standard production chassis Twenty four teams competed in the 2006 British Championship and the is retained, although reinforcing subframes is permitted. Many 2007 season, which is sponsored by Delphi Diesel Aftermarket, kicked teams also move the engine position, so the traditionally very off in mid-April at Pembrey in South Wales. For more information on front-heavy truck ends up with a virtually mid-engined layout. truck racing, including the full season’s calendar, go to www.btra.org. In addition, shortened suspension travel and racing shock absorbers, which are adjustable to suit varying circuits and conditions, give the latest racetrucks much higher cornering speeds than their predecessors.

Although all the major components sit low in the chassis, the standard truck cab is retained, which means the driver is still sitting high up – more than a metre from the ground. This is always a shock for experienced car racers getting behind the wheel of a racetruck for the first time: one guest driver described his first outing as, “Like driving a block of flats from the sixth floor”! 0-60 in under four seconds, a top speed of 192 mph and a consumption of 22 mpg Porsche and BorgWarner develop the first VTG™ for a petrol engine

When drivers hear the word ‘Porsche’ and ‘turbo’ in the same sentence, it instantly conjures up images of real power for pure driving pleasure. The newest Porsche 911 Turbo, launched last year, is certain to meet these high expectations. It is the first petrol-engined vehicle ever to use a VTG™ turbocharger for greater efficiency and performance.

Up to now, variable turbine geometry (VTG™) has been reserved for diesel engines. The technical challenge for its application in a petrol engine was to develop materials that can handle the significantly higher exhaust gas temperatures of up to 1000°C found in these engines. Working together with Porsche, BorgWarner Turbo & Emissions Systems succeeded in developing a turbocharger with VTG™ technology for the 911 Turbo. The adjustable turbine vanes sit right at the heart of the turbocharging system and can be closed to generate high boost pressure at low revs and low exhaust flow rates. This vastly improves response and pick-up at low speeds compared to conventional turbochargers. Additionally, the petrol engine with VTG™ displays significantly greater efficiency over the entire performance range compared to today's standard turbochargers with wastegate. This in turn leads to further improvements in fuel consumption over a wide rev band.

This cut away Despite its similarity to the diesel version, the engineers at section shows BorgWarner had to completely redevelop the cartridge - the the variable most important component of the VTG™ - to meet the high vanes which demands in terms of exhaust gas temperatures. The close at particular challenge was to find highly heat-resistant low revs materials with the right tribological and thermal expansion properties that would allow the necessary surface qualities and tolerances to be manufactured reliably. In the course of development, new aerospace materials were also used, some of which had never before been used in car or turbocharger design. The world’s first turbocharged diesel boxer engine

Subaru has always been a great believer in the horizontally-opposed engine, claiming that the opposing in a flat effectively balance out each others' vibrations, giving smooth, seamless, fluent power Aerospace materials help cope with the intense heat delivery right through the rev range.

Even more important, the design is A massive boost shorter and shallower than other The 3.6 litre engine in the new 911 Turbo has two BV50G turbochargers with engines, which means they are more electrical VTG™ actuation. These help the 6- boxer engine generate just compact, lightweight and very rigid. A over 470bhp, some 59bhp more than its predecessor. Nominal torque has also horizontally-opposed engine can also been increased by 44 lb.ft to over 450 lb.ft. At the same time, the engine be fitted way down in the chassis, to developers have been able to expand the rev band in which this massive power is give a very low centre of gravity. This available, to further improve the already legendary performance of the iconic reduces body roll for safer cornering sports car. On the previous model, maximum torque was available between 2700 and also enhances handling precision and 4600rpm. The new engine generates its 457 lb ft of torque in the entire during rapid manoeuvres such as a range from 1950 to 5000rpm. sudden lane-change on a motorway.

With manual transmission, the new 911 Turbo sprints from 0-60 in under four seconds – and the version with the new Tiptronic S is 0.2 seconds faster. The top speed of both versions is 192mph. Perhaps more impressive than the increase in power is the lower fuel consumption of the new 911 Turbo, which averages an impressive 22mpg (20.8mpg in the Tiptronic S).

Optional Overboost Facility

The flexibility of the 911 Turbo can be enhanced even further with the optional Sport Chrono Package Turbo, available for the first time. By engaging the Sport button adjacent to the gear lever, this feature enables the driver to activate a short-term turbocharger ‘overboost’ function at full , giving an increase in boost pressure in the mid-speed range by 0.2 bar for up to ten seconds and improving torque by 60Nm to 680Nm. In this configuration, the time required by the 911 Turbo with manual transmission for intermediate acceleration from 80 to 120kph (50-75mph) is reduced by 0.3 seconds to 3.5 seconds. Now, for the first time, the company Driving technology forward with VTG™ has introduced a turbocharged diesel Following the successful premiere in the Porsche 911 Turbo, engine which, it claims, is a highly rigid BorgWarner expects its VTG™ technology to find a broader base unit with low levels of noise and of petrol engine applications in the next ten years. Compared to vibration. Not only does this eliminate other boosting concepts, VTG™ represents the best price- the need for a balancer shaft to performance ratio after the wastegate turbocharger. It offers the counter uneven combustion pressures performance and dynamic behaviour of a larger normally aspirated and general roughness, but Subaru’s engine with significantly lower fuel consumption. Hans-Peter Schmalzl, first turbo diesel is as compact as its Vice President Technology at BorgWarner Turbo & Emissions Systems petrol sisters and combines unusually predicts that, "Gasoline engines with exhaust gas turbocharging and direct strong pulling power at low engine fuel injection will enjoy the same kind of success as diesel engines". speeds with high-rev throttle-response. Did we Garrett VNT™ Turbochargers meet at To repair or not to repair – is it worth the risk? MechanEx? By Trevor Cass, Garrett IAM Product Support Engineer (Europe, Middle East & Africa)

The turbocharger aftermarket has traditionally been a place where a BTN Turbo recently took two stands at customer had the choice of buying a brand new or a remanufactured turbo. MechanEx – an exhibition organised However, the rapid development of the turbo, alongside developments in and promoted by Professional Motor engines, fuel injection systems and engine management, has meant that Mechanic held at Sandown Park. If you missed it, you should look out this must change. for future events, as it is an invaluable In order to comply with strict emission controls, our turbos have become much opportunity for anyone involved more technologically advanced – which, in turn, means they are more difficult to with service and mechanical repair repair. Because the VNT™ is far more complex than a conventional turbo, repair to meet suppliers of aftermarket and remanufacture can’t be done correctly without specialist equipment tools, diagnostic equipment and and information. Indeed, even with the equipment in our factory, we ourselves components. don’t remanufacture. We know that new units are the risk-free option.

One of our stands was manned by Sales When we build new turbos we calibrate them to three decimal places, with a Managers Peter Hesham and Peter number of checkpoints used to ensure correct operation. A remanufactured turbo Allpress to show visitors how BTN can would also need to be calibrated to the same degree of accuracy. But calibration cope will all your turbo requirements. of a VNT™ turbo on its own is completely worthless without the critical first stage The other stand displayed Mark being completed: setting the ‘minimum vane open’ position. Hosken’s 350bhp Audi TT (profiled in the last edition of Revolution) along The Garrett VNT™ components are manufactured to extremely tight tolerances with the commercially available turbo but, due to the large number of parts and the clearances needed for the safe and upgrade kit that allows him to achieve the power.

During the exhibition we met more than 300 workshop owners and operators, all of whom went home with a goody bag that included a Putting a face book of vouchers worth £100 off replacement turbochargers from BTN. In this issue of Revolution, we’d like to introduce some of the ‘backroom boys’. If we didn’t meet you there, we hope to do so at the next show! Ray Jones Senior Workshop Supervisor Ray Jones oversees the running of the workshop and deals with warranty and technical issues. He has been with BTN for 28 years, having joined as a machinist shortly after finishing his apprenticeship at British Leyland. Amazingly, he still remembers the part numbers of the turbos he first worked on all those years ago, citing the Holset 3LD and Garrett T04 commercial vehicle ranges as the most popular. Following the launch of the Saab 99 (TC03), Porsche Mark Hosken gets down to (k26, 3LDZ) and Audi (k26), he’s seen discussing the finer points the market for passenger car turbos of his 350bhp Audi TT kit grow dramatically. In his spare time he

Ray Jones efficient operation of a VNT™, each individual turbo has to be tested and adjusted after assembly, to ensure that it meets the engine manufacturer’s specified flow setting. Any disassembly of the VNT™ turbo will mean that the minimum vane open setting must be reset before the calibration process can be completed.

We set the minimum flow vane position by using a calibrated turbine flow bench which measures the actual airflow through the vanes of every single VNT™ that we make, and allows us to Setting the minimum flow vane position set and lock the minimum flow position to suit each application. • Excessive boost pressure, which may cause blown and It is not possible to set the calibration of the actuator to OE physical engine damage. specification until the minimum vane open position is set. The ‘real’ cost of fitting an incorrectly remanufactured turbo Without a turbine flow bench, a remanufacturer can only guess You should also consider the real cost of replacing a turbo if the that the airflow is correct: the turbo may operate, but it is remanufactured one that you have fitted fails. Your supplier highly unlikely that it will work to its optimum efficiency. may replace the turbo free of charge, but who pays for the time The consequences to fit the second replacement? And if the failed remanufactured The outcome of not being able to set the minimum vane open unit damages other parts of the engine, who would be liable for position accurately may be: the repair? • Conflict with the engine management system, leading to error Garrett will not sell spare parts for VNTs for these reasons: messages or running in ‘limp home’ mode. it’s just too big a risk. Your official Garrett will sell • Low flow/pressure, which can cause poor response, poor genuine new turbos, to exactly the same specification and overall performance and increased emissions – and possibly an quality as supplied to the original equipment manufacturer, MoT failure for your customer. with a valid guarantee. They back this up with many years of • Over-rich diesel fuel/air mix, which can cause excessive specialist turbo knowledge to help you. temperature, damaging the turbo and engine. • High flow/pressure, which can lead to overspeeding of the turbo, Why risk a remanufactured VNT™? Use a new unit, for wheels bursting and consequential damage to turbo and engine. safety’s sake and for the sake of your business. e to the name....

enjoys DIY, motor racing and old cars – he used to own and output and 25% new units to 25% remanufactured and 75% show a beautiful 1958 Wolseley 1500. new. Paul lists his interests as music, books, wine, beer, cricket, football, golf, tennis and rugby. Only a professional planner Paul Whight could find the time for all of these! The man responsible for Progress and Planning Control is Paul Whight, who schedules everything between Sales and the Paul Harding Workshop, as well as looking after exchange stock. He cut his Paul Harding is also a Workshop Supervisor. His turbo experience teeth (sorry) in the spans just over twenty dentistry industry as a years, the last eleven having technician: he describes been spent with us. He likes many similarities involving to keep fit, working out processes and tooling, but regularly and taking his dog says that our tools are for long power walks. He much bigger! In his ten also enjoys travelling and is years with BTN, he has a fan of the Superbike noted the shift from selling Championship and 75% remanufactured motorbikes in general.

Paul Whight Paul Harding SPIN DOCTOR

Oil matters - don’t make any mistak

It’s not an exaggeration to say that oil is the lifeblood of an engine, and nowhere is it more important than in the turbocharger. Oil fulfils three essential functions: it lubricates, cools and cleans metal parts that would otherwise overheat and grind to a very messy halt!

The turbocharger is subjected to temperatures in excess of 1000º Centigrade: it spins at up to 200 000rpm; it has to withstand severe pressure differentials; and it is designed and manufactured with tolerances measured in ten-thousandths of an inch. It is estimated that more than 90% of turbo failures are caused by oil problems, the most common of which are:

• Contaminated or dirty oil, which leads to bearing scratching or scoring and causes excessive bearing wear.

• Lack of lubrication: as the turbo runs at very high speeds, even a momentary loss of oil pressure can cause overheating and destroy the bearing system. Lack of lubrication results not only from low oil pressure, but also from kinks and/or clogs in the oil inlet line.

• Use of the incorrect oil.

Two other oil-related problems can occur through driver misuse. Prolonged engine idling can cause the turbo to rotate without producing boost. Consequently, a vacuum within the turbine tries to pull oil past the turbine-side oil seal and into the turbine housing, which can lead to failure of the oil seal. Hot engine shutdown may cause the oil to coke up inside the oil drain, forcing the oil out through the turbine and compressor seals.

Handle with care

In the next issue When fitting a replacement turbo, take care to ensure that the seals are properly seated and the inlet and outlet of Revolution; hoses are of the correct and kink-free. Refill the engine with the correct volume of oil (flush the engine first, what would you if necessary) and test the turbo for operation and leaks thoroughly. like to know? Selecting the right oil for the engine is important. Mineral or synthetic? Mineral oil (i.e. that which comes out of Ask us and we’ll the ground and is refined) used to be the only option. It offers good basic protection for a wide range of engine write an article. types but it does require changing frequently. Synthetic oils (i.e. those that come from a laboratory, albeit with a mineral oil base) are especially designed to circulate quickly from cold, reduce wear and last longer, but there is a price premium. The middle ground is semi-, i.e. a blend of mineral and synthetic oils, which falls between mineral and synthetic both in performance and price. Be very careful about mixing oils in an engine. Not all lubricants Build up to Le Mans 2007 are compatible and if you top up with the wrong type, you can do a lot of damage. Check with the manufacturer or distributor • Audi R10 TDI triumphs at Sebring again to be absolutely certain that the lubricants you are thinking of • Acura/Honda shows promise • Peugeot continues testing mixing are compatible. By achieving an impressive victory in the 12 Hours of Viscosity Sebring (USA) on 17th March, Audi made a perfect start Viscosity is a way of measuring the ‘thickness’ or ‘flowability’ of into the 2007 motorsport season with its revolutionary oil. Oil thins when heated and thickens when cooled. Viscosity diesel sports car. It was the eighth victory in a row in the classic American endurance race for the Garrett-boosted is classified by the Society of Automotive Engineers (SAE): the manufacturer from Ingolstadt. The 2007-spec R10 TDI ran lower the number, the thinner the oil and so the more suitable without the slightest technical problem during the whole it is for cold temperature use. 12 hours on the extremely demanding track. A monograde is oil whose viscosity is defined at only one temperature, either high or low. A multigrade must meet both high and low temperature viscosity requirements simultaneously. A viscosity modifier additive produces a thickening effect at high temperatures but is dormant at low temperatures. akes with yours Despite the Audi being the fastest car on the track, newcomer Acura/Honda was able to get into the lead on a This makes multigrades a popular year-round choice for hot number of occasions with its 150kg lighter LM P2 cars. summers and harsh winters. Multigrades are recognised by the dual viscosity designation (e.g. 0W-40 where the ‘0W’ is the low temperature or winter designation and the ‘40’ is the high temperature designation). Because turbos spin so fast even when the engine is cold, there is a move by manufacturers towards specifying oil with a low viscosity such as ‘0W’ so that it gets to the turbocharger bearings quickly. Again, ensure that you comply with the manufacturer’s recommendations, to prevent damage. Meanwhile, back in Europe, the Peugeot 908 HDi FAP, also Keep it clean boosted with a Garrett turbo, made its maiden official outing at the pre-season Le Mans Series test session at Finally, a word about keeping the lubricant free of Paul Ricard HTTT (High Tech Test Track). Since the car’s contaminants. Many oils these days have a detergent additive unveiling on 10th January, Team Peugeot have completed that keeps the engine clean, but in so doing they transport three chassis and the car’s workout at Paul Ricard was its small particles of carbon (‘coke’) around the system. The older sixth and final run before the opening race of the 2007 Le Mans Series at Monza. the oil or the more overheated the engine has become (overheating accelerates the production of coke), the more particles will be held in the oil flow. The will trap some of these particles but if the oil isn’t changed according to the manufacturer’s recommendations, it actually becomes abrasive – think of it as a thin grinding paste – and that will do your turbocharger bearings no good at all!

We said at the beginning of this article that oil is the lifeblood The prestigious Le Mans 24 hour race, takes place on 16- of the engine. Think how a hospital deals with a transfusion, 17th June. This will be the first time that the Audi and Peugeot go head-to-head and, if the Acura/Honda fulfils selecting only the right blood group and handling with extreme its promise in the American Le Mans series, it should be care. Adopt the same principles with your oil and you’ll there too. Watch this space in the next edition of eliminate many of the causes of turbo failure. Revolution to see who triumphs! Is the diesel boom Turbos help make the greenest cars reaching its peak? On 15th March 2007, the Environmental Transport Association (ETA) announced the winners of its 2007 Car Buyers’ Guide, the definitive guide to Britain’s greenest cars.

Over the past decade, diesel engines have The ETA guide lists 2500 new cars and provides a star-based ranking system that become increasingly popular in European gives consumers an overview of any vehicle’s performance against the following passenger cars: in 2005, more than half categories: power; carbon dioxide emissions; fuel consumption; noise; and safety. the cars sold in Europe were diesel-powered The overall winner, for the second year in a row, was the Honda Civic Hybrid. and global production of turbochargers Jaguar’s XJ 2.7 diesel, with its twin Garrett turbochargers, won the luxury class. This reached 13.5 million units: a four-fold car demonstrated its fuel economy credentials last year by covering 1000.2 miles on increase over ten years, with Europe a single tank of fuel – the average fuel consumption hitting 53.5mpg, with accounting for around three-quarters of emissions of just 139g/km of CO2. that growth. The most environmentally friendly 4 x 4 award went to the Toyota RAV4 5 door The just-auto report ‘Global market review of diesel manual, which is fitted with a Garrett Toyota turbo. automotive turbochargers and For the first time this year, ETA – forecasts to 2012’ suggests that diesel share introduced an Innovation Award in order in Europe will reach a peak of 55% in the to champion a motor manufacturer that early part of the next decade, but it will has demonstrated environmental then plateau as new technology (or perhaps innovation through a new product, or we should say new applications for project, or in its production processes. existing technology) begin to take their slice The winner of this first award is Saab, of the market. for its BioPower flex-fuel technology just-auto believes that superchargers will (see article in this edition of Revolution). make a comeback, due to the increasing development of GDI engines. GDI stands for Gasoline Direct Injection, as used on the Garrett two-stage turbo boost for PSA Volkswagen TSI engine described in this issue of Revolution (VW call their injection system In 2003, PSA Peugeot Citroën engineers set Garrett the challenge of uprating the performance of their 2.2 litre to match the power output of an FSI). The principle behind GDI, borrowed from equivalent 2.5 to 3 litre single turbocharged unit. diesel engines, is direct injection of fuel into the , at very high The result is the first parallel sequential dual-stage turbocharger system in the pressure. The evaporation cooling effect world, now in use on the Peugeot 407 and 607, and the Citroën C5 and C6. Garrett already offers two-stage turbocharging, using a serial sequential allows a high compression ratio, to deliver configuration where a smaller high pressure turbo works in advance of a larger excellent power and economy. GDI engines booster. For this task, however, Garrett and PSA set out to explore the possibilities could create a significant market for of two small turbos working side-by-side at high rpm, but only one delivering the superchargers, which allow them to display power at low revs. consistent performance across the engine’s The new system delivers up to 30% more torque compared to the standard 2.2 rev range. A supercharged GDI engine could litre diesel engine and improves third gear acceleration in the 30kph to 50kph reach the same output and emission ratings range by 30-50%. In addition, it gives excellent fuel as a diesel engine with less auxiliary efficiency; better emission control; and a small equipment, and therefore at a lower cost. package size to fit under the bonnet. We’ll be watching developments closely but Garrett stated that it sees the parallel sequential without too much concern: there are literally architecture as a key building block for dual-stage millions of vehicles, both private and turbocharger systems, not to replace serial commercial, using turbochargers, and there sequential arrangements but to increase the will be for some years to come. And as long flexibility of its product portfolio. as they are on the road and still coming out of factories, there will always be a market for BTN Turbo Limited, BTN House, Arundel Road, Uxbridge Trading Estate, Uxbridge, replacement turbochargers. Middlesex UB8 2RP, England Telephone:+44 (0)1895 466666 . www.btnturbo.com VGT™ is a registered trademark of Cummins Turbo Technologies VNT™ is a registered trademark of Honeywell International VTG™ is a registered trademark of Borgwarner Automotive