Newsletter of Lehigh Valley Corvair Club Inc. the fifth wheel NOVEMBER 2020 HTTP://WWW.CORVAIR.ORG/CHAPTERS/LVCC ESTABLISHED 1976 Inside this issue Ejector Cooled Engines. 2 The Story Ejector Cooled Engines. 3 The Cars Ejector Cooled Engines. 4 The Concept LVCC October 5 Teleconference Notes Corvair Crossword 6 Puzzle. The Clues Corvair Crossword 7 Puzzle. The Grid Time to Pay Up! 7 Late Dues Reminder ‘Tis the Season for… 8 MICE! LVCC Officer Contact 8 Information Next LVCC Teleconference - January! Tech Topic: Removing 9 As a matter of long-standing tradition, we refrain from having Old Rusty Fuzzies meetings during the holiday season because the 4th Wednesdays Corvair Classified Ads 10 of November & December are so close to Thanksgiving, Christmas from NJACE & Hanukkah. And so it is this year, too. We’ll be having our next teleconference on Wednesday, January 2, 2021. Meanwhile, we’ll keep you entertained with our regular monthly newsletters. And as always, reach out to us if you need tech advice or have questions about keeping your Corvair alive. The Fifth Wheel is published monthly by Lehigh Valley Corvair Club Inc. (LVCC), a chartered chapter for the Cor- vair Society of America. We accept articles of interest to Corvair owners for publication. Classified advertising of interest to Corvair owners is available free of charge to all persons. Commercial advertising is also available on a fee basis. For details, email our newsletter editor, Allan Lacki, [email protected]. PAGE 2 THEFIFTHWHEEL NOVEMBER 2020 Ejector Cooled Engines. - The Story Tatra, based in the Czech Republic, It’s so simple. There are no moving with equations, diagrams and discus- manufactured cars with air-cooled en- parts. No fan belts, no blowers, and sion about the theory, but several im- gines for a long time, going all the way being air-cooled, none of the stuff as- portant basics stand out: back to 1923. They began with the in- sociated with water-cooled engines. troduction of the Model T-11, designed And by eliminating all that, Tatra 1. The proper length and diameter of by Hans Ledwinka. So it should be no picked up an extra twenty horsepower the ejector chamber depends on the surprise they figured a way to eliminate on its 2.5 liter V8s. (A good turbo- energy needed to draw cooling air the engine cooling blower and thereby charger would have given a better across the cylinder heads and barrels. increase net horsepower. And they did boost but at the expense of higher This, in turn, depends upon the density it using…engine exhaust? What?! stress on engine components). and thickness of the cooling fins on those components. Tatra experimented Tatra developed a cooling system There are a couple of slight disadvan- with ejector chambers of different di- where the exhaust headers and engine tages. To maximize the cooling effect, ameters and telescoping lengths to ex- shroud outlets are all routed to a cylin- huge megaphone outlets called plore the effects. drical mixing chamber, also known as “diffusers” must be affixed to the ejec- an “ejector”, where the exhaust gases, tor chamber outlets. They take a lot of 2. The efficiency of the ejector cham- traveling at high velocity, create a par- room. And Tatra never did figure a ber is improved if the incoming ex- tial vacuum that sucks cooling air out way to integrate mufflers into the sys- haust nozzles – i.e. the header pipes of the engine shroud. Julius Mackerle, tem. So, between the megaphone- outlets – are spread across the full di- Tatra’s chief engineer, named it the shaped diffusers and open exhaust, the ameter of the chamber’s inlet. This “ejector cooling system”. engines are really, really loud! Fine works much better than a single nozzle for racing, but not on the street. in the center. To achieve this effect, Although no venturi is involved, the Tatra formed the nozzles into star- underlying theory is like a carburetor. In 1961, a few years after he left Tatra, shaped outlets as illustrated on Page 4.. It’s an application of Bernoulli's princi- Mackerle authored a 476-page book ple, which states that an increase in the named Air-Cooled Motor Engines. 3. “Diffusers” – megaphone-shaped speed of a fluid occurs simultaneously Originally written in Czech but trans- outlets, also help to increase the effec- with a decrease in static pressure; in lated into English, it covers just about tiveness of the ejector chambers. The other words, a partial vacuum. In our every aspect of air-cooled engine de- diameter of each diffuser inlet should case, engine exhaust is fluid that causes sign. It includes a chapter devoted to be the same as the diameter of the ejec- the suction to occur. the ejector cooling system. It’s filled (Continued on page 5) NOVEMBER 2020 THEFIFTHWHEEL PAGE 3 Ejector Cooled Engines. - The Cars Tatra 607-2 open-wheel racer. Circa 1957. Tatra 607-2 chassis showing ejectors & diffusers Tatra 603-B5. Marathon de la Route class winner The diffusers are enormous! Test driver Jakub Rejlek explains how they work. Side view. IECO trombones have nothing on these!. PAGE 4 THEFIFTHWHEEL NOVEMBER 2020 Ejector Cooled Engines. - The Concept From Mackerle’s book. Tatra V8 with ejectors Everything you ever wanted to know about air- cooled engine design, including ejector cooling. Above: This view shows the front of the engine with the ejector chambers removed. Note the star- shaped tail ends of the exhaust header pipes. Left: Tatra V8 turned on its side. The silver pods cover the exhaust headers to retain heat for the ejector chambers. The actual ejector chambers are the short dark-gray cylindrical tubes. The long dark gray megaphones are the diffusers. NOVEMBER 2020 THEFIFTHWHEEL PAGE 5 (Continued from page 2) tor chamber outlet. And based on ex- five minutes into the video) enceCall.com. Rich Greene, Randy perimentation, the taper should be Kohler, Al Lacki, Larry Lewis, Fred about 8 degrees. This explains why the https://www.youtube.com/watch? Scherzer and Jeff Strausser were on the diffusers on Tatra racing cars are so v=HBiSJWAKSp4 line. huge. (Refer to the photos and you will see!) For those of you who are interested in The teleconference lasted from 7:30 to vital statistics, the final arrangement of 8:38 PM. FreeConferenceCall.com 4. The exhaust piping from the cylin- the T 603 ejector-cooled V8 engine is enables meeting participants to either der head to the ejector chamber must be shown on Page 4. The engine has a call-in by telephone or log-in using a short and not exposed to excessive 75 mm bore and 71 mm stroke. This computer with both audio and video. cooling to preserve the kinetic energy equates to 2,500 cc or 150 cubic The latter is much like Zoom. Most of of the exhaust gas flow. On Tatra’s V8 inches – about the size of an early Cor- us used FreeConferenceCall’s video racing engines, the tubular exhaust vair engine. An ejector is mounted on feature this time around. headers are completely enclosed for each side of the engine; one per cylin- this purpose. der bank. The diameter of each ejector Larry Lewis said there will be a car chamber is 5.5 inches (140 mm). The show at Silver Creek on Sunday, No- Tatra installed an ejector cooling sys- length, including the diffuser vember 1st. It is replacing the usual tem on it’s open-wheel T607-2 Mo- (megaphone) is 33.4 inches (850 mm). Roll-Out at Riegelsville this year. nopost racing car in the 1950s but the The discharge temperature from the Communist Party never allowed it to ejector is 320 degrees F (160 °C) at Jeff asked when Das Awkscht Fescht compete outside Iron Curtain. full load. At 7,500 RPM and with a will be held in 2021. The dates are compression ratio of 12 : 1, the per- August 6, 7 and 8. Jeff also wanted to It wasn’t until the 1960s that Tatra was formance of the engine is 200 horse- know which day LVCC members put allowed to strut its stuff in the West. power. their Corvairs on display. Rich Greene And they chose to do it at the Marathon said most members only bring their de la Route, an 84-hour endurance race Sources: Corvairs out on Sunday, which is Club at the Nürburgring track in Germany. Mackerle, Julius. Air Cooled Motor Day for Das Awkscht Fescht. Randy That’s eighty-four hours of high-speed Engines. London, Cleaver-Hume Kohler makes arrangements every year racing on one of the most tortuous Press Ltd, 1961 for LVCC to have a section of the courses in the world. Think “LeMans http://www.eurospares.com/ show field just for Corvairs on Club times 3”. graphics/engine/a-c-e-searcheable. Day. pdf As can be imagined, the emphasis was http://archive.commercialmotor. But Rich pointed out that some mem- on supreme reliability, not speed. Ro- com/article/24th-november-1961/45/ bers put their cars on display on Fri- bust production cars, not fragile proto- air-cooling-by-exhaust-ejector day, Saturday or all three days. Rich is types, were the choice for competing at https://www.roadandtrack.com/car- one of those people. the Marathon de la Route, and Tatra culture/news/a29403/this-tatra-race- was no exception. It chose it’s T-603 car-conquered-the-nurburgring-for- Al Lacki mentioned that membership luxury sedan - the only model in pro- 84-hours-straight/ renewals are way down this year.