I would wager that not one of those cars that attend the Pure Stock Drags are actually pure stock, many of them not even close. I know guys running stroker kits, ported heads and manifolds, etc. Us old guys know what those cars ran when they were new...…....and stock.
You would lose that wager . I know for certain that there have been two 100% stock muscle cars at the event in the past because they were our cars. They were concours restored show cars are were 100% stock in every way possible. That explains why we were running mid and high 14s while most others were quicker. While the PSMCDR rules do allow for some modifications, you are right that many (most?) violate the rules in some way. Thankfully they pair you with a car that runs a similar time so the races are usually close.
Calculating gear ratios they are equal. To start off with. Great video. 3.64x2.48=9.02 4.10x2.20=9.02 2 beautiful cars. Chevelle runs real good for a stocky ocky looking 70. Those intakes were horrible. That GSX is immaculate. Both 1970! Best year to me. Great to see them both out racing, doing what GM built them and we rebuild em for. Running.
No disrespect but there hasn't been a really well tuned SS396 Chevelle at the pure stock race. The weights they mentioned also are not accurate. The GSX is lighter than the Chevelle. I own each and they have been weighed. What Doug says is true.
I just rebuilt a BBC 396 a few months ago for a guy and on the engine dyno it made 403 HP @ 5,800 RPM, which reminds me that I'm still waiting to hear what the torque was. But it was basically close to factory build, no head porting, 9.5:1, the pistons were probably 10 to 30 grams a piece less than factory. The only thing different was the hyd. roller mild 230*/230* @ .050" cam IIRC it had around .530" something of lift and it has roller rockers topped off with a Holley IIRC. So with a flat tappet cam, factory carb and stamped steel rockers the thing would probably be closer to 360 to 375. Dyno guy guessed it would probably max out at maybe 375 HP, always good to come in 28 HP higher than what the dyno guy guesses. Could of probably got another 5 to maybe 20 HP with a bit more tuning or trying a different carb or playing with carb spacers? But that wasn't a priority for the guy, he basically wanted to have ran on the dyno to make sure all would be well so he was sure he only had to install it once. Oh yeah, it was built for a '69 Chevelle SS, it should run good in that car.