Ok I am finding after 5 years in a nonwing sprinter that gear selection is some kinda of voodoo mystery!!! Here is my issue, for the last four(4) years I have been running an ASCS engine on a high backed 1/4 mile that 99% of the time has a sticky cushion to run on. I always ran a 6.50 gear and turned the engine between 7800 and 8200. Now I had to unload the ASCS engine and am now currently running a home built iron head engine that my dad and I built, now this current engine has all good solid parts in it callies crank, oliver rods, and JE 13.5to1 pistons. The cam is good to 7600ish RPM. SO this is what i did...Its in the SAME car, SAME setup, SAME track, SAME driver but instead of 6.50 gears I put in 6.37`s wanting to DROP RPM, and what happens?? I go out there and turn 8900 in hotlaps!! I thought maybe my tach was wrong but it did it the whole night. SO I put a set of 6.20`s in the next race and still turned 8600, now Im down to 5.95`s and still turning just over 8k. Everyone else in the pits is running 6.40`s the 6.80`s, so I guess my question is: is there some wierd engine curve thing that I am missing?? I have pulled my hair out over this deal for the last 12 weeks I am at the point now that if I run any taller gear I will not be able to go slow enough under pace/caution laps! Any help/advise would be greatly appreciated. Thanks Pat

?????? Help me out here fellas I'm at a loss
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Just a thought, but maybe a trip to a dyno would be in order, be a shame to blo a good motor, just because you don't have any info on it, and you'll get a comparison on your instruments! Bob!