I am still not sure which way to go on the rear gear selection. Right now I have a 12 bolt posi main with 3.31 gears. I have a 396 with about 500hp on a 28 inch tire. I run around town in first and second gears. Turnpike I am in third. Rarely hit fourth.

I really need a different gear but I am not sure of what to put in the car. The 4.10 would be nice but I don't want to be at 6000 rpms at 50 mph (not that bad but you know what I mean). The 3.31 that is in it now definately has to go. Any suggestions on this.


thanks
kissel-

 

What do you want to use the car for.... driving around town, or running at the track?

For the track, pick the gear ratio that puts you near the engine's rpm limit in 4th gear (assuming you have a 1:1 4th gear), with the 28" tire, at the trap speeds the car is capable of running.

As far as street driving, what are the limits of your tolerance to rev's on the freeway? Right now, in 4th gear at 70mph you are turning 2,780rpm. Changing would give you:

3.42 - 2,874
3.73 - 3,134
4.10 - 3,445
4.56 - 3,830

Only you can determine what you can live with. You might want to try one of the online gear calculators to help you evaluate the various options.

 

any idea what the top speed would be at 6000 rpms in fourth?

thanks
kissel

(still trying to figure out the calculator thing)

 

http://www.smokemup.com/auto_math/mph_range.php

 

thanks.....this should help a little


kissel