My best friend owns a custom car shop. He drives a C-5.. I've raced him lots with my car stock and no NOS.. I kicked his butt. He has the hard-top lightweight coupe.
Why did I beat him. Driving. I didn't spin the wheel all through first, I shifted fast and where the gears where most optimal. If we were to keep going, he would have passed me up like I was standing still.
So much depends on the driver. If they can't keep the momentum of a good start, their car will seem slower than somebody else who could drive a little better. Had nothing to do with difference in power. Also Vette's are VERY different when in comes to comparing An automatic to a standard. We've dynoed about 50 vettes. Seen many differences. Stock Auto to stick. The auto loses about 25 hp to the wheels. Auto tranny eats up more hp. and with the taller gearing, it slows it down even more. just more racing factors to consider.
My best 1/4 time when completely stock, sea level- cool outside 60F. (Houston Raceway Park) '91 NSX ALL stock - 13.268 @104.5mph 1.9 60' time. My best when I first got the car, 13.9. Did the car get faster? NOPE, I did. : )
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Stock gears, stock everything - custom intake made by me and a couple of Borla mufflers welded in line. Lots of NOS.. Custom Crappy clutch.. Still goes fast. Falling apart at the same time. I'm fixing everything soon though (Dented fender un-painted spoiler)