I have a 1994 Z28 6 speed with stock gearing I think. I would like to know what gear ratio would give me the best 1/8 mile times?

 

4.56 or 5.12, good for 1/8 mile runs, but not too great on the road. lol

 

What about for 1/4 mile runs?

 

4:10's will do pretty good and still be streetable,not very good on the freeway though.

 

For best ET the engine should all revved out in 3rd or 4th gear (depending on your final drive ratio) just as you cross the speed trap at the end of the run. A car geared for optimum strip results is usually a PIA on the highway, but with your two overdrive gears it may be tolerable.

 

i have a 94 z28 six speed just like u and i have 411s in the rear end...i love them, not so great in the rain or in the mpg section tho. all things you should consider if yours is a dd...

 

Where can I purchase a new gear ratio? Can I go straight from stock gear ratio to 3:73s?

 

you can get new gears from jegs. but it is not a simple job. is this car a DD? if so just get some 4:10s lik every six speed guy does. if it has a real purpose look up a gear calculator and put in all the needed info. lik said above you should go through the traps at the top of 4th. you'll need tire size and then enter the gears itll give u a mph at a certain rpm. for example. im using a 27" tire and a six speed im gonna spin it to 6800 i entered that info and 3.70 gears is wat i need to cross the traps at 140mph. its a bit much mph but wont be to far off.

 

so you guys are suggesting for a dd go with 4:10's???

 

373s will work just fine on a dd. thats what i would go with. u will have the best of both worlds. low gears and acceptable milage.