hey guys ive been hunting around for a solution to my trannys long gears and stumbled across a 4.9 final drive set for a good price what id like to know is will the 4.9 final in my stock ls geared tranny require me to shift into fifth? what would be the max mph attainable on this set up as im already at 126-128 in the quarter thanks.

car makes 490hp/326trq weights 2500lbs with a 8200rpm limiter on a 24.5 slick

 

Get the 4.785 instead. the gearing is much smoother for the LS transmission than the 4.9 final drive. you'll stay in powerband quickly, but you'll be in 5th gear even faster. LS with a 4.9 in 5th gear is GREAT crusing gear on the highway, but since this is a race setup, you may want to go to MFactory's calculator to look at options.

 

Thanks for the reply shodan! this just happens to be within 30 minutes of me and just under half price of new set. what did you mean by the 4.7 being smoother BTW?

 

Use this gear calculator:

http://www.teammfactory.com/gear-calculator

That will help you determine if it will work for you.
Final drive is something you will need to test and explore..if the price is right..go for it! Worst case you can sell or trade if it does not work out for you.

 

ok so ive run the numbers and it turns out this final drive will be out of gear at 126mph in fourth.so my question is, if my 60 foot is **** and im spinning out of the hole will that add mph at the end of the track because im trapping 127-128 on 2.0 60's basically id like some input on this purchase. Id rather stay in fouth gear but if i have to shift so be it. do you guys and gals on here think with even a 1.6 -1.8 60 foot id be able to get through the towers?