I would go with a B&M Shift Improver kit or the TCI equivalent.

 

Great calculator THumpin.

I had 3.00 in my 8", bent the axles and blew the diff. Then borrowed a set of 3.20's while i got together a more bullet proof setup.

I ended up with a 31 spline 9", billet axles with 3.5's in it at the suggestion of my engine builder. It fries tires off the line into 3rd and jumps from 65 to 90mph in no time when I want to pass a truck. Great fun, but fuel consumption is s**t and it's revving too hard at 75 which is normal speed for me. It dropped my top speed by 20mph.

doing it again, i would agree with atomsk, because if the motor is any good, your 1/4mile times are about the same because there is one less gear change. But i'd also seriously consider the 3.2 as that was a good compromise...felt faster, but 300 less revs at highway speed.

 

well, maybe if i had a 289 i would feel differently though

but a posi rear with stock gears should hold up just fine to my clevo

 

if your planing on upgradeing to a 5 speed someday i would save your money and not get a shift kit. i would gear 3.73s with a 5 speed.

 

im planning to keep it auto. but want to add a shift kit. does anyone know where to get one?

 

I just had a 3.70 put in. I have a T5 but I've still heard from some people that I still should have went 3.55. Anyhow, it's not out of the shop yet so I don't know how it will run. I'll post later.

 

emperor...the 8.8's came in the foxy body mustangs...the classics just had straight 8" rear ends.

Adrian, go with a B&M Shift kit for your C4....I have one in mine and it makes a world of a difference. Hard, positive shifts and it rides out the rpms a little more. Also I like shifting on my own too even when I am cruisin around town, and the shift kit helps with that. I would also recommend an aftermarket shifter too, either a ratchet style or a gate shifter...that way if you are shifting you wont accidentally jump into N, or worse...Rev.