Quote:
Originally Posted by ALMACK
I would be curious how a racer will get around the SFI bellhousing rule with the transmission arrangement in that car
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I apologize for going a little off-topic here, but for anyone considering running a manual transmission race car without a clutch can, whether the rules require it or not, I submit the following. Please learn from my error(s) in judgement:
Back in the '80s, I ran an NHRA Pro ET normally-aspirated rotary Mazda door car twice a week at two local drag strips. There was no commercially-available SFI Spec 6.1 bellhousing. There was also no SFI Spec 1.1 flywheels or clutches available.
The set-up that worked the best for me, was a stock cast iron flywheel, with a stock pressure plate, and a fairly lightweight clutch disc with a solid (unsprung) hub and no marcel spring between the facings. I experimented with various metallic pucks on the disc.
The NHRA rule book at that time said that solid-lifter manual transmission cars had to have a clutch can, and since the rotary has no lifters, I was able to get through tech without one, even though I was launching, shifting, and going through the lights at about 9,000 rpm.
Then in 1990, a flywheel/clutch explosion at the top end nearly cut the car in half.
It was an un-necessarily exciting ride, for a car that only went 111 mph or so. It sounded like a bomb going off inside the car. In addition to the concussion, the wind was suddenly whistling through the car, which was full of smoke and what I initially thought was flames (but turned out to only be sparks from severed battery cables). It blew the latch off for the front-hinged hood and blew the hood up momentarily, until the wind made it flop back down. It blew the brake master cylinder right off the firewall, so I had no brakes. I also had no engine compression braking, since it vaporized everything between the engine's rear main seal and the transmission's front bearing. It oiled down my slicks, which made steering kind of exciting, as my right hand wouldn't work (it had been resting on the shifter when the explosion happened, which stunned my right arm up to the elbow). Thank God I had routed my fuel line outside the front sub-frame stampings (for this exact reason), or I would have been on fire with absolutely no way to stop, with nothing but a single-layer 3-2A/1 jacket to protect me. I was afraid to look at my feet, because I thought I had lost them. Fortunately, the rotary engine is so small, that the entire clutch and flywheel are located forward of the firewall, so my feet were never in line with the shrapnel.
I will never make a mistake like that again.