korndawg

Due to their reputation and being a fellow ISU grad only 75 miles away, I'm going to have Quick Performance build me a 9" for my Chevelle with LSA swap. With the upgrade cam, pulley, and HX, I can only guess the car is going to make around 625 hp/tq at the wheels. It'll be mated up to a 4L80e trans with a Circle-D 2800 triple disc stall. This car is 100% street. It's for a lot of show and a lot of go! Question is what should I choose for a rear gear w/ that setup. Old gear setup w/ my 4L60e and factory Chevelle 12 bolt was a 3.73. I really didn't have too much complaint about that ratio. The 4L80e does have quite a taller first gear tho. Just not sure which the optimal ratio would be with my current setup. Thoughts?

Also, for axles. I'm quite sure a 31 spline will be plenty, however moving up to a 35 spline is the same price. Is there a noticeable power loss at the wheels w/ the beefier and stronger axle? Or just do it once and go with the 35 spline? Limited on those 2 choices as I'm going to go with the Wavetrac diff. Thanks!

MidwestChassis2

iTrader: (1)

If you can purchase 35spl axles to work with your combination it is always best. For gear selection there is a few online calculators that will come in handy to help you determine the best gear ratio for you.