# Naturally Aspirated Vehicle Performance



## MCSL (Jan 30, 2005)

Fastest 4-cylinder NA Racecar

140 cu in, 2294cc Honda K20 Inline-4

350 hp @ 12000 rpm

Standing ¼-mile: 8.14 sec @ 163 mph









Pocket Rocket: Andrew Holt's Honda-Powered Comp Eliminator Dragster


Andrew Holt has taken a different path to go fast in the crazy world of Competition Eliminator by using Honda power to rocket deep into the eight-second zone!




www.dragzine.com



























Fastest 4-cylinder NA Production Superbike with bolt-on mods

Kawasaki ZX-14R

1441cc Inline-4

240 hp

593 lb

Standing ¼-mile: 8.87 sec @ 158.6 mph



https://blog.brocksperformance.com/the-louisville-slugger-part-3-2012-zx-14r-dragbike-com-project-regular-guys/





https://blog.brocksperformance.com/kawasaki-zx-14r-12-16-information-page/












8-cylinder F1

2011 Red Bull RB7-Renault

2.4-liter V8

750 hp @ 18000 rpm

1257 lb

Standing ¼-mile: 9.2 sec



https://www.carwow.co.uk/blog/carwow-quarter-mile-400-metre-1320-ft-time-drag-race-leaderboard


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## Autoputzer (Mar 16, 2014)

Back in the early 2000's the production cars with the highest specific output from a naturally aspirated engines were the V8 Ferrari of the day, a Honda S2000, and an E46 M3. The Honda was so tweaky that it was hard to drive, so they punched the displacement out, but widened the torque band instead of increasing the power.

I rented an S2000 out in LA back then. But, I'm not really a convertible guy, and it was too small. But, I had a blast with that car. I ordered an M3 when I got home.


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## MCSL (Jan 30, 2005)

Fastest Small Block 8-cylinder NA Racecar

400 cu in, 6555 cc Mopar V8

1200 hp @ 11000 rpm

2230 lb

Standing ¼-mile: 6.846 sec @ 200.05 mph

Bob Book, owner of Book Racing Engines has been churning out all-motor monsters for some of the fastest naturally-aspirated racers in the world. His engines own records in the United States as well as Australia. Book builds an assortment of naturally-aspirated engines from different manufacturers, but this Mopar-based mill seems to be the king of the small-blocks he’s built.

“This engine makes 20-30 more horsepower more than a GM or Ford small-block and it uses more air on the dyno than other engines we’ve built of the same cubic-inch. We don’t do anything totally different with this engine, it’s just a better platform for naturally-aspirated racing,” Book says.

400 cubic-inch small-block Mopar engines centered around an R4 block from Mopar – the same one you can buy from a Chrysler dealer’s parts department. On top. a set of billet cylinder heads built on the Mopar P4 architecture by Tom Slawko at Slawko Racing Heads. The billet cylinder head is permitted in Aussie Pro Stock, so these are Slawko’s take on the design and are the best of the best, according to Book.









Book Racing Engines Smashes NHRA Small-Block N/A Record


Brandon Huhtala became the first driver to break the 200 mph mark in a naturally aspirated small-block in the NHRA




www.enginelabs.com























































Fastest 2-rotor NA Racecar

Mazda Miata

Mazda 13B Rotary

Standing ¼-mile: 8.17 sec @ 160.18 mph





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30th anniversary of Le Mans victory commemorative site


In 1991, Mazda became the first rotary engine manufacturer in the world and the first Japanese manufacturer to take overall victory in this prestigious race. In the lead up to the 30th anniversary of this momentous occasion in 2022, we have created a commemorative website to introduce the...




www.mazda.com









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Rotary Tech Tips: Additional Tuning Tips






www.racingbeat.com









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rotaryengine.com | Rotary Engine Specialists | Mazda Performance | RX7 Specialties


Wholesale direct! Celebrating our 20th year in business. Specializing in Rotary engines and parts. Builders of the most reliable personal and race engines. Worldwide shipping!




www.rotaryengine.com













10 Things You Need To Know About Rotary Tuning - Haltech


If you own, race or tune rotary powered cars this might be the most important article you'll ever read!



www.haltech.com













New Spin: Mazda Files Patent for New-Gen Rotary Engine, Here’s What It Tells Us


We've pored over the patent, and here's what we learned. Read more at Car and Driver.




www.caranddriver.com













Rotary Engine 16X, Next Generation RENESIS


Next Generation RENESIS (Rotary Engine 16X) In 2007, the 40th anniversary year of Mazda’s rotary engine, Mazda announced a plan to develop the next generation Renesis (16X). The aim was to im…




rotarypowercrew.wordpress.com














Fastest Electric Production Car

Rimac Nevera

1914 hp

4740 lb

Zero to 60 mph: 1.9 sec

Standing ¼-mile: 8.582 sec @ 167.51 mph









Watch the 1900-HP Rimac Nevera Set an 8.52-Second Quarter-Mile World Record


The electric hypercar is officially the fastest accelerating production vehicle.




www.roadandtrack.com


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## XChallengeRdr (Jul 15, 2020)

650cc NA Methonol/Nitro
100hp
214mph
1956









60 Years Ago, Johnny Allen Brought the World Motorcycle Speed Record Home


By today’s world speed record standards (376.363 mph), Johnny Allen’s 1956 record of 214.4mph seems tame. But it truly was a feat for Triumph and Allen.




ultimatemotorcycling.com


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## dukedkt442 (Feb 12, 2013)

A friend of mine drives around in a clapped out ‘89 AWD Mitsubishi Gallant with mismatched wheels, ripped bumper covers and rusty fenders. The car runs in the 8s, courtesy of the engine he built for it. 2.x Liter turbo 4 that pulled up to 750 hp on the 4 wheel dyno before ALL 4 tires broke loose on the rollers at around 5k RPM. The car had more. A LOT MORE. I am a MOPAR fan but it’s hysterical to RUN, not walk, away from HellCats, which are no slouches. The car has mind/universe-altering thrust. Insane. 


Via the interwebs


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## MCSL (Jan 30, 2005)

Neutron Honda K24 V8









Neutron Engines' Honda-based K48 V-8 promises to be a pint-sized screamer


With a goal of 10,000 rpm and over 700 hp, the K48 should be a real screamer for its 5.0-liter package. Read the story of this V-8's unlikely birth.




www.hagerty.com













Ultimate Honda K24 Guide – Everything You Need To Know


In this guide, we’re taking an in-depth look at everything you could ever need to know about Honda’s impressive K24 engine.




www.drifted.com


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## MCSL (Jan 30, 2005)

Race Car

























Porsche has revealed its new 718 Cayman GT4 RS Clubsport that will be available to race in the IMSA Michelin Pilot Challenge in 2022. The mid-engine racer, based on the Cayman GT4 RS road car, was unveiled at the Los Angeles Auto Show.



Length: 4450 mm (175.2 in)

Width: 1810 mm (71.3 in)

Height: 1238 mm (48.7 in)

Weight: 1330 kg (2932 lb)



Like the road car, the racing 718 Cayman GT4 RS Clubsport is equipped with a 4.0-liter, six-cylinder boxer engine taken directly from the Porsche 911 GT3 Cup race car and produces 500 horsepower – 75 more than the previous GT4 Clubsport model. It has a seven-speed, dual-clutch transmission, replacing the previous GT4 Clubsport’s six-speed gearbox.



“We thrive on competition and will always push for improvements,” said Volker Holzmeyer, president and CEO of Porsche Motorsport North America. “This is what our customer teams expect of us and what we demand of ourselves at Porsche. Acting on their feedback, we’ve made the new 718 Cayman GT4 RS Clubsport more capable than ever. It’s quicker, even more rewarding and confidence-inspiring to drive – exactly what drivers competing in the IMSA Michelin Pilot Challenge and SRO series need to be successful.”



Porsche first offered the Cayman GT4 Clubsport of the 981 generation in 2016, with the next-generation model – based on the 718 Cayman GT4 – debuting in 2019. The strong demand for these vehicles is due to their low running costs.



In addition to the stronger 4.0-liter engine (18 percent more powerful than its 3.8-liter predecessor), the new 718 Cayman GT4 RS Clubsport achieves maximum power at 8,300 rpm – 800 rpm higher than previously. It results in a wider, more usable power band for the engine, improving drivability. The seven-speed transmission also features shorter gear ratios than on the GT4 Clubsport.



Revised damper technology on the 718 Cayman GT4 RS Clubsport offers optimized responsiveness and improved body control, significantly impacting handling. Two-way racing adjustable shock absorbers with improved valve characteristics, as well as adjustable double-blade anti-roll bars, front and rear, are among the updates. Ride height, camber and toe are also adjustable.



Special NACA ducts in the front lid feed air efficiently to the large race braking system with 380-millimeter, multi-piece rotors that are vented and slotted. The Porsche Stability Management-System is programmed specifically for the track and includes a switch for traction control, ABS (anti-lock braking system) and updated stability control.



The aerodynamics of the 718 Cayman GT4 RS Clubsport have also been enhanced in great detail to increase downforce, calm air flow over the car and optimize air flow at the rear diffusor.



The previous 718 Cayman GT4 Clubsport was the first series production race car to use body panels made of sustainable natural-fiber composites. This material is used even more extensively on the new GT4 RS Clubsport. In addition to the doors and the rear wing, the front lid, fenders, aerodynamic components at the front and the steering wheel consist of this material. The use of this flax-based fiber as an alternative to carbon-fiber composite can be evaluated in racing for potential use in road cars.











718 Cayman GT4 RS Clubsport | Porsche Motorsport Hub


The entry into GT racing: faster than ever. The new 718 Cayman GT4 RS Clubsport.




motorsports.porsche.com




































The 718 GT4 RS Clubsport will make its racing debut at Daytona next month.









Team TGM to race new Porsche 718 Cayman GT4 RS Clubsport in 2022


After competing in a variety of series at both the professional and club level, under several manufacturers, the one thing that was certain about the Team TGM racing program, there has always been a Porsche as part of their racing efforts.




www.teamtgm.com


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## MCSL (Jan 30, 2005)

Road Car















































Porsche's 718 range will go all-electric at some point in the future. So Porsche's GT department figured it should build the ultimate internal-combustion Cayman while it still could. The 718 GT4 RS is not a limited-production model.



Length: 175.4 in

Width: 71.7 in

Height: 49.9 in



The 718 Cayman GT4 RS makes 493 hp and 331 lb-ft to the 911 GT3's 502 hp and 346 lb-ft, but this engine isn't detuned. The slight dip is due simply to the need for longer exhaust pipes. The only significant difference between the engines in the GT4 RS and GT3 is with the intake because of the packaging needs of a mid-engine car. That intake is a marvel, too, as the car now breathes through carbon fiber inlets that replace the Cayman's typical rear quarter windows, in addition to the inlets behind the doors.



The runners from those intakes actually pass through the cabin, just behind the seats, into a giant airbox that sticks out from where the rear parcel shelf used to be. The intake manifold itself is variable length, and as with the current 911 GT3, the GT4 RS has individual throttle bodies, though they are now vertical instead of horizontal.



Basically, the cabin of the GT4 RS will be a resonance chamber for the most sonorous of flat-sixes. "You can orchestrate the noise like a conductor," Andreas Preuninger, head of Porsche GT cars, tells us. "The intake noise is all real. There's nothing synthetic. There's nothing coming from some speakers—it's how it is. And you hear the air rushing in creating these burbles and these noises depending on your load and RPMs. It's so entertaining."



The 991-generation 911 GT3 engine had a cast-aluminum dry sump oil tank that would not fit in a Cayman without major reengineering. But the new 992-generation 911 GT3 engine’s composite dry-sump tank is designed to fit the Cayman. Everything else, including the individual throttle bodies, titanium con-rods and rigid finger-follower valvetrain is the same as you get in the GT3.



Unlike other 718s, you can see the new engine because Porsche removed the traditional engine cover and put a wall and window between the cockpit and the engine compartment. Doing so was necessary to add engine air intakes where the quarter windows used to be. There's still a cargo area behind the engine. The side intakes are now fully dedicated to cooling the new engine.



The 9,000-rpm engine is backed by Porsche's PDK seven-speed dual-clutch transmission. All of Porsche's RS models are now PDK-only, as dual-clutch transmissions make for quicker lap times. The GT4 RS' PDK gearbox features shorter ratios for better acceleration. A mechanically locking limited-slip differential is standard.



The MacPherson-strut suspension has been heavily reworked, with stiffer springs, new faster-reacting electronically adjustable adaptive Bilstein dampers, and spherical ball joints replacing all rubber bushings. Ride height is 1.2 inch lower. There's a greater range of camber and toe adjustment, so you can really tailor the handling to your preference. The front track width is 0.24 inch wider thanks to new fenders, while rear track widths are the same as the GT4.



Getting all the extra horsepower to the ground are standard Dunlop SportMaxx or Michelin Pilot Sport Cup 2 tires. All are mounted on the same size 20-inch wheels as the standard GT4, but now on forged aluminum center-lock wheels. Ultra-sticky Michelin Pilot Sport Cup 2 R tires—which were fitted to set a 7:04.5 lap time around the Nürburgring Nordschleife—are available as an option. The brakes are similar to the current GT3 with steel rotors as standard and PCCB carbon-ceramic rotors as an option.



Front Tires: 245/35ZR20

Rear Tires: 295/30ZR20



Aerodynamics has been heavily revised here, with the GT4 RS capable of 25 percent more downforce than the GT4 when everything is set to maximum attack - 220 lb downforce at 120 mph. The rear wing is much larger, and gets GT3-style swan-neck mounts to help clean up the airflow underneath. The front splitter is bigger, too, with vanes on the side ahead of the wheels. There's an adjustable front diffuser (4 positions)—which must be adjusted in concert with the rear wing (3 positions) to maintain aero balance. The maximum downforce setting will give the best lap times on most race tracks.



Air vents above the front fenders evacuate high pressure air from the wheelwell and reduce the front-end lift that air causes. Like the previous 911 GT2 and GT3 RS, there are NACA ducts integrated into the front hood for brake cooling. Remarkably, all this extra downforce doesn't come at the expense of drag.



Weight savings is also a big focus for RS cars, and at 3227 pounds, the GT4 RS weighs around 50 pounds less than a PDK-equipped GT4, despite all its extra hardware. The hood and front fenders are made from fiberglass reinforced plastic, and the rear window is made from lightweight glass. Interior changes, like a reduction in sound-deadening, simpler door panels with pull straps replacing handles, and lighter carpet also contribute to weight savings.



If you want the lightest possible GT4 RS, go for the Weissach Package. It includes carbon fiber hood, side blades, mirrors, window scoops, rear wing and titanium exhaust tips. It also replaces the standard steel half roll cage with a titanium version. The package should save another 40 pounds, getting you to 3187 pounds total. 20-inch forged aluminum wheels also come standard with the Weissach Package, while the forged magnesium wheels are available as an option.














All of these enhancements compared to the 718 Cayman GT4 make the GT4 RS the most uncompromising and sharpest member of the 718 family. This is particularly evident on the Nürburgring Nordschleife. During the final phase of set-up adjustments, Porsche racing driver Jörg Bergmeister lapped the 20.832 km track in 7:09.300 minutes. The GT4 RS conquered the shorter 20.6 km version, which previously served as the benchmark, in 7:04.511 minutes – 23.6 seconds faster than the 718 Cayman GT4.











The new Porsche 718 Cayman GT4 RS


The Porsche 718 Cayman GT4 RS is the new flagship model in the 718 family – an uncompromising driver’s car designed to impress with its lightweight construction, extremely agile chassis set-up, sophisticated aerodynamics and unique soundtrack.




newsroom.porsche.com







Nürburgring Nordschleife Lap Time



McLaren 720S V8 Turbo 720hp _ 7:08.34



Corvette C7 Z06 V8 Supercharged 650hp _ 7:13.90



Corvette C8 V8 500hp _ 7:29.90



Tesla Model S Plaid 1020hp _ 7:30.90








Official Lap Times Records Nürburgring Nordschleife


Official Nürburgring Nordschleife lap times records for street legal vehicles and other cars.




www.biggarage.de















2020 Chevrolet Corvette C8 Nürburgring Lap Time Has Been Revealed


The new mid-engine C8 Corvette breathes down some pricey exotics' necks around the iconic 'Ring, as its lap time has finally snuck out into the open.




www.motortrend.com


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## MCSL (Jan 30, 2005)

Porsche 718 GT4 RS

























Engine

Naturally aspirated boxer 6

Bore:102.0 mm

Stroke: 81.5 mm

Displacement: 3,996 cc

Max. power: 493 hp @ 8400 rpm

Max. engine speed: 9000 rpm

Max. torque: 331 lb-ft @ 6250 rpm

Aluminum engine block and cylinder heads

Water-cooled with thermal management

VarioCam Plus variable valve timing and lift

Dry-sump lubrication with separate engine oil tank

Oil supply with fully variable pressure oil pump, 7 suction stages, oil centrifuge and additional oil supply via the crankshaft

Direct Fuel Injection (DFI)

Variable intake manifold with two switchable resonance flaps and six individual throttle valves

Flow-optimized stainless steel lightweight sport exhaust system with 2 tailpipes made of stainless steel in High Gloss Black

Airbox cover in black with "GT4RS" logo in Silver

Forged titanium connecting rods



Gearbox

7-speed Porsche Doppelkupplung (PDK) with short gear ratios and sport setup

Rear-wheel drive

Porsche Torque Vectoring (PTV) with mechanical limited slip differential

GT specific gear selector with manual shifting

Auto start/stop function

PDK Sport button for more dynamic and shorter shift times

Launch Control



Chassis

Lightweight spring-strut front axle (incl. helper springs), anti-roll bar, and suspension mountings ball-jointed

Lightweight spring-strut rear axle (incl. helper springs), anti-roll bar, and suspension mountings ball-jointed

Electromechanical direct steering with variable steering ratio

Adjustable race track chassis with RS-specific spring rates and shock absorber tuning.

Electronically controlled damping system with 2 manually selectable modes, "Normal" and "Sport"

Porsche Active Suspension Management (PASM) variable damper system with sport setup and ride height lowered by 30 mm

Dynamic transmission mounts

Adjustable chassis (toe, camber, and anti-roll bars)

Porsche Stability Management (PSM) including ABS, with two switchable stages (ESC OFF and ESC+TC OFF)



Wheels & Tires

20" 718 Cayman GT4 RS wheels in Dark Silver

Front: 8.5J x 20 ET61 wheels with 245/35 ZR20 tires

Rear: 11J x 20 ET50 wheels with 295/30 ZR20 tires

Tire Pressure Monitoring System (TPMS)

Ultra high performance summer tires (UHP)

Tire sealing compound with electric air compressor

Wheel center caps with "RS" logo







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Home | Porsche Experience Center - Los Angeles, CA


Drive the best vehicles Porsche has to offer on a world-class track designed to test your limits. Our various experiences are crafted with one thing in mind– the thrill of the drive.




www.porschedriving.com













Porsche Driving Atlanta FB Title


Porsche Driving Atlanta Description




www.porschedriving.com









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Home | Porsche Track Experience - Birmingham, AL


Porsche’s official U.S. driving school, where driving enthusiasts have the opportunity to pilot the latest Porsche models and hone skills with a professional instructor.




www.porschedriving.com















Porsche Racing Experience - Dr. Ing. h.c. F. Porsche AG







www.porsche.com













Porsche Track Experience


Porsche Experience




experience.porsche.com













Downloads


The latest brochures can be downloaded here.




experience.porsche.com


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## MCSL (Jan 30, 2005)

1978 Mazda RX-7 Bonneville Racecar



Using an 80-cubic-inch 13B in place of the stock 70-cubic inch, 100-hp 12A engine upped the caliber of our threat to 326 horsepower.

Key Racing Beat mods were peripheral intake ports fed by a huge Weber carburetor and exotic aluminum-impregnated-carbon apex seals.

At the salt, our target was the 167.208-mph E/GT record held by a Corvette.



After an overnight engine swap, we were back for more on Speed Week’s Monday morning.

Forty seconds running at over 10,000 rpm in two directions earned our second record book entry.

Adding a rear spoiler we believed might be worth a few more mph necessitated additional qualifying and record runs.

The last pair of passes averaged 183.904 mph, earning a new E/GT record in Car and Driver’s and Racing Beat’s names.



Power

326 hp @ 9750 rpm (at sea level)

260 hp (at Bonneville, 4000 ft elevation)



Redline: over 10000 rpm











Rotary Reverie: 35 Years on the C/D Wankel-Engine Racing Beat







www.caranddriver.com







Mazda RX-7 Endurance Racecar



The Mazda RX-7 was used for Mazda’s first factory entry at Le Mans 24 Hours, but it was overall victory at the 1981 Spa 24 Hours – the first for a Japanese brand – that really put the RX-7 on the map. Alongside winning the British Touring Car Championship in 1980 and 1981, these victories for the British TWR team firmly established the RX-7 in the UK.



The distinctive howl of the RX-7’s twin-rotor powerplant rocked race tracks in Europe and beyond from the beginning, winning the British Saloon Car Championship’s 1,600-2,300cc class in 1980 and 1981 and demonstrating its reliability by capturing the chequered flag at the 24 Hours of Spa, also in 1981.



It was a golden age elsewhere, too. In the US, the RX-7 won over 100 IMSA races, more than any other model of any brand, dominating the GTU class (under 2,500cc) including the 24 Hours of Daytona for an unparalleled 12 consecutive years (from 1982-93). The RX-7 also proved itself in the Australian Endurance Championship, winning from1982 through 1984, as well as that country’s Bathurst 12 Hour (champion 1992-95).



Australia: RX-7 vs V8 Commodore








1981 Spa 24-hours race overall winner









MOTORSPORT: The Mazda RX-7 that won the 24 Hours of Spa


With a small but passionate maker of sporty cars and oddball engines taking center stage at this year’s Goodwood Festival of Speed, all manner of Hiroshima steel could be found on the show gr…




japanesenostalgiccar.com











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The race that changed my life: Pierre Dieudonné, the 1981 24 Hours of Spa | Inside Mazda







www.insidemazda.co.uk

























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Remembering the Mazda RX-7: Win Percy recalls motor racing’s giant killer | Inside Mazda







www.insidemazda.co.uk















John Phillips: Ten Cars That Most Surprised 10 C/D Editors


My test car's V6 ate its balance shaft four blocks from the Reatta Craft Centre.




www.caranddriver.com









http://amv-prod-aut.s3.amazonaws.com/assets/s3fs-public/AW_TBT_20180104_MazdaRX7.pdf


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## MCSL (Jan 30, 2005)

Mazda RX-7 Endurance Racecars



Thanks to the advantages of the Wankel, the first-generation RX-7 (FB) had a lightweight, compact engine, located behind the front axle, and could make use of a sharper bonnet than its rivals and take greater advantage of its dynamics, with less polar moment of inertia.



The 1st-gen RX-7 also received a new version of the 12A engine developed in the RX-3 in racing. A new trochoid (the rotor) was used for the first time, with a different treatment to harden its surface. Made of aluminum, the casting of this material was made on a steel sheet already cast as a "perimeter". This steel sheet received a chromium-plated treatment on the outside to guarantee the hardness of the trochoid.



In addition, this chrome layer was applied with a special porous treatment to improve lubrication, which allowed the use of steel rings instead of the carbon plated ones of previous versions. The engine was therefore cheaper to produce, but it was also more leak-proof, used less fuel and was more powerful and reliable.



The combustion chambers embedded in the trochoid were also asymmetrical, to favour the combustion process, driven by a double sequence spark plug system, which worked differently depending on the engine load (at low load, only one spark plug was activated) to also favour a more progressive combustion at low throttle loads.



To avoid the problem of the RX-3, the new RX-7s were fitted with a new intake air filtering system, as well as a reinforced exhaust manifold system. The 12A engine had stopped its development in the Japanese Touring Car Championship, as Mazda's home country silhouettes had switched to the new larger displacement 13B engine.



The racing 12A was by then down to 250 horsepower, but by 1979, for Daytona, Mazda would create a new specification, under the name 12B. This new derivative employed thicker engine apex rings and single rather than double side rings to reduce friction. Coupled with the advanced side and peripheral port system and its set of intake butterflies, the 12B was capable of delivering 265 horsepower at 8,500 rpm with enough reliability to withstand a 24-hour race.



And so it proved. In its debut at the 24 Hours of Daytona, the Mazda RX-7, against all local odds, took the GTU class double, with an overall fifth place finish for the faster of the two Hiroshima cars.



It was the first victory in a 24 Hours race, at least category victory, for a Wankel engine in the world, and it was achieved in the competitive debut of the RX-7, achieving just the effect that Mazda wanted: beating the Nissan Z in front of the American public.



That 1979 would see two more GTU wins for the RX-7 in two more sprint events (Sears Point and Portland), with even more powerful engine versions designed to last fewer hours, with 275 horsepower at 9,500 revolutions. Interestingly, the RX-7 had faced the so-called second Oil Crisis in the United States at its launch (remember, late '78), but fortunately for Mazda, the combination of price, sporting success and American consumer appetite made the FB a commercial success.



That year, 1979, Nissan would still take the IMSA GTU title, but the next five years (80, 81, 83 and 84) would be mercilessly dominated by the RX-7. In any case, before that dominance, 1981 would see another endurance race win, an outright victory that Mazda wanted at the time more than any other: Spa Francorchamps.



Competing in the GTU class for cars with engines smaller than 2.5-litres it won the 24 Hours of Daytona at its first attempt in 1979. It then took the GTU championship for seven years on the trot. From 1982 it also lifted the GTO class (for cars with engines bigger than 2.5-litres) for 10 consecutive seasons. And while the class structures might have changed, the RX-7’s success remains undiminished: it has won more IMSA races than any other model in history.










Daytona Road Course 24-hours race



1979 Daytona (3.84 miles)

RX-7 (#7) Race: 5th overall, 1st in GTU, 617 laps

265hp 12B 2-Rotor RX-7 GTU (#7) Fastest Lap: 2:05.403





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Daytona 24 Hours 1979 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1979




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1979.html





1980 Daytona (3.84 miles)

RX-7 (#77) Race: 8th overall, 2nd in GTU, 618 laps

12B 2-Rotor RX-7 GTU (#17) Fastest Lap: 2:02.323





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Daytona 24 Hours 1980 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1980




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1980.html





1981 Daytona (3.84 miles)

RX-7 (#98) Race: 7th overall, 3rd in GTU, 606 laps

12B 2-Rotor RX-7 GTU (#82) Fastest Lap: 2:02.556





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Daytona 24 Hours 1981 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1981




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1981.html





1982 Daytona (3.84 miles)

RX-7 (#77) Race: 4th overall, 1st in GTO, 644 laps

RX-7 (#98) Race: 6th overall, 1st in GTU, 640 laps

13B 2-Rotor RX-7 GTO (#77) Fastest Lap: 1:59.913

12B 2-Rotor RX-7 GTU (#92) Fastest Lap: 2:03.491





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Daytona 24 Hours 1982 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1982




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1982.html





1983 Daytona (3.84 miles)

RX-7 (#7) Race: 3rd overall, 1st in GTO, 598 laps

RX-7 (#92) Race: 12th overall, 1st in GTU, 544 laps

13B 2-Rotor RX-7 GTO (#7) Fastest Lap: 1:56.421

12B 2-Rotor RX-7 GTU (#92) Fastest Lap: 2:01.367





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Daytona 24 Hours 1983 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1983




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1983.html





1984 Daytona (3.87 miles)

RX-7 (#76) Race: 12th overall, 1st in GTU, 574 laps

RX-7 (#38) Race: 14th overall, 3rd in GTO, 569 laps

13B 2-Rotor RX-7 GTO (#38) Fastest Lap: 2:09.601

12B 2-Rotor RX-7 GTU (#82) Fastest Lap: 2:11.902





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Daytona 24 Hours 1984 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1984




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1984.html







https://www.racingbeat.com/gallery/Car%20and%20Driver%20Jan%2081.pdf













A Tale of a Race Winning Rx7 Chassis


During the past Pandemic Christmas holiday, I decided to retrofit a decades old slot car race track for the digital age. My young son had been absolutely captivated with it nearly two decades ago a…




jimchungblog.com













Kent Racing Mazda RX-7 Wins IMSA Award at Amelia Island Concours | IMSA







www.imsa.com


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## MCSL (Jan 30, 2005)

IMSA GTO 2-Rotor RX-7
























































IMSA Lights Champion

1985: Jim Downing (USA), Downing Argo-Mazda

1986: Jim Downing (USA), Downing Argo-Mazda

1987: Jim Downing (USA), Downing Argo-Mazda












































Goodwin Racing -- David's Black Hopper RX7


Street, Autocross and Track Performance for your Mazda, Fiat 124, Toyota-Subaru BRZ/FRS/86.



www.good-win-racing.com









https://autocatalogarchive.com/wp-content/uploads/2017/04/Mazda-RX-7-1988-USA.pdf





Ahead of the 1983 season, Argo branched out from single seaters to sports cars. The move came at the request of North American distributor Hugh Kleinpeter, who wanted to tap into the lucrative IMSA GTP market. Dubbed the JM16, the first Argo sports racer was designed by company founder Jo Marquart with the help of Nigel Stroud. It proved particularly successful in the new-for-1985 IMSA GTP Lights category. Encouraged by the great results in 1985, a new car was readied for 1986.



Like its predecessor, the new JM19 featured a full length aluminium honeycomb monocoque, which allowed for a variety of engines to be installed. Where the JM16 featured pull-rod actuated in-board springs and dampers at the front and push-rods at the rear, the new Argo boasted a more straightforward outboard spring and damper setup. Designed by Achim Storz, the JM19 bodywork was made from carbon-fibre composites to further reduce weight.



Argo's principle customer for the JM19 was Jim Downing, who ran Mazda rotary engined cars in the IMSA Lights championship. The Mazda engined cars, however, proved most successful with Downing repeating his 1985 domination with the JM16 in 1986 and 1987 with his rotary engined JM19s.



Chassis: JM19-107-GTP

Fitted with a Mazda rotary engine and fielded by Jim Downing, this Argo JM19 was first raced in the 1985 season finale at Daytona. In the hands of Downing himself and John Maffuci, it finished 13th overall and first in class. In 1986 Downing and Maffuci also managed to score class wins at Road Atlanta, Riverside, Portland and Sears Point. It was raced through to the 1989 season when it returned to its winning ways with class victories at Watkins Glen and Portland.





http://www.mulsannescorner.com/downing.htm


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## MCSL (Jan 30, 2005)

Mazda RX-7 and Rotary-powered Endurance Racecars



Mazda History at Daytona 24 hours (23 class wins): 

1 GTU Touring win (1975)

13 GTU wins (1975/79/82/83/84/85/86/87/88/89/90/91/92/93 – 12-IN-A-ROW)

2 GTO wins (1982/1983)

4 Camel Lights wins (1985/1986/1990/1993)

1 SRP win (20001)

2 GT wins (2008 & 2010)



Making the most of the more lenient IMSA regulations, Amos Johnson of Highball Racing set about constructing a new RX-7 inspired GTU racer with full permission of Mazda. Although the work started late in 1984, the target for the car's first race was the 1985 season opening Daytona 24 Hours. Remarkably, the car was actually still being built at the track ahead of practice but by the end of the weekend, the all-new GTU car had clinched a debut class victory.



Although homologated as a GT car, Team Highball's new RX-7 was the first GTU car built around a bespoke spaceframe chassis. To still meet the homologation requirements, the chassis was clothed in a body that just about matched the silhouette of the first generation Mazda RX-7. Suspension was by double wishbones at the front and a live rear axle. As raced at Daytona, the RX-7 featured a mildly modified version of the RX-7 road car's 12A engine, mated to a five-speed gearbox.



For the car's Daytona debut, Johnson was joined by regular co-driver Jack Dunham and Japanese racing legend Yojiro Terada. Johnson continued to race the car throughout the 1985 IMSA Championship but after the debut victory, no more (class) wins were scored. Now joined by Dennis Shaw, Johnson and Dunham were back in top form at the next Daytona 24 Hours. Starting a lowly 51st, they placed eighth overall, which was enough for another class win in the gruelling race. Like in 1985, no further class wins were scored in 1986.



Ahead of the 1987 season, Team Highball substantially reworked the car to match the recently introduced second generation RX-7. In addition to the revised body panels, the car was also fitted with a new Type 13B engine. This was eventually upgraded with 13J rotors and a fuel injection system developed for a six-cylinder engine powering Cessna airplanes. In this guise, the very compact engine produced around 345 bhp.



The heavily revised Team Highball RX-7 continued the tradition and won the GTU class for a third consecutive time in 1987, this time with Johnson, Shaw and Bob Lazier behind the wheel. Johnson also won the GTU class at Riverside. During its fourth season, the car was driven to yet another Daytona class win and also to a class win at Sebring for the first time. For the success with his RX-7, Johnson was awarded with a works drive in 1990. The GTU car was leased out and scored its fifth class win at Daytona.



With five wins at Daytona, the Team Highball RX-7 is the single most successful chassis ever (the second best has 'just' three class wins). With a class win at Sebring also on its tally, the GTU RX-7 is also the most successful endurance racing chassis. With its many wins, the Team Highball car contributed considerably to the over 100 IMSA class wins scored by the RX-7.



Chassis: RX-7-1

The first of two RX-7s built by Team Highball, this car was raced extensively from the 1985 Daytona 24 Hours through to the 1991 season. In 69 outings, it scored nine GTU class wins including a record setting five at Daytona and one at Sebring.





























































































Daytona Road Course 24-hours race



1984 Daytona (3.87 miles)

Argo JM16-Mazda (#63): 9th overall, 8th in GTP, 579 laps

RX-7 (#76) Race: 12th overall, 1st in GTU, 574 laps

RX-7 (#38) Race: 14th overall, 3rd in GTO, 569 laps

Lola T616-Mazda (#68) Fastest Lap: 2:05.909

Argo JM16-Mazda (#63) Fastest Lap: 2:06.032

13B 2-Rotor RX-7 GTO (#38) Fastest Lap: 2:09.601

12B 2-Rotor RX-7 GTU (#82) Fastest Lap: 2:11.902



1985 Daytona (3.56 miles)

Argo-Mazda (#93) Race: 10th overall, 1st in Lights, 602 laps

RX-7 (#53) Race: 11th overall, 2nd in GTO, 599 laps

RX-7 (#71) Race: 12th overall, 1st in GTU, 599 laps

330hp 13B 2-Rotor Argo-Mazda (#63) Fastest Lap: 1:58.895

RX-7 GTO (#96) Fastest Lap: 2:01.038

RX-7 GTU (#76) Fastest Lap: 2:04.295





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Daytona 24 Hours 1985 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1985




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1985.html





1986 Daytona (3.56 miles)

Argo-Mazda (#13) Race: 7th overall, 1st in Lights, 600 laps

RX-7 (#71) Race: 8th overall, 1st in GTU, 597 laps

Tiga-Mazda (#9) Fastest Lap: 1:54.497

RX-7 GTU (#38) Fastest Lap: 2:01.438





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Daytona 24 Hours 1986 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1986




 www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1986.html





1987 Daytona (3.56 miles)

RX-7 (#71) Race: 10th overall, 1st in GTU, 642 laps

Badger-Mazda (#36) Race: 14th overall, 3rd in Lights, 621 laps

RX-7 (#38) Race: 19th overall, 6th in GTO, 572 laps

450hp 3-Rotor RX-7 GTO (#38) Fastest Lap: 1:54.364

Argo-Mazda (#63) Fastest Lap: 1:56.726

RX-7 GTU (#75) Fastest Lap: 2:02.467





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Daytona 24 Hours 1987 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1987




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1987.html





1988 Daytona (3.56 miles)

Argo-Mazda (#63) Race: 13th overall, 2nd in Lights, 615 laps

RX-7 (#71) Race: 15th overall, 1st in GTU, 598 laps

RX-7 (#38) Race: 16th overall, 3rd in GTO, 597 laps

RX-7 GTO (#38) Fastest Lap: 1:50.119

Argo-Mazda (#63) Fastest Lap: 1:54.562

RX-7 GTU (#71) Fastest Lap: 1:59.721





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Daytona 24 Hours 1988 - Racing Sports Cars


Information and listing for race Daytona 24 Hours 1988




www.racingsportscars.com







http://www.classicscars.com/wspr/results/imsa/imsa1988.html




































































Pettit Built Engines


Since 1990, 30 years and counting well over 2000 Pettit Built Rotary Engines have been sold for street and race use around the world, earning Pettit Racing a reputation for unsurpassed quality and outstanding reliability. Proven to deliver performance & longevity beyond expectation time after...




pettitracing.com


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