cwilgo63

I've got an 81 z28 with a 350. it has a ported stock alum. intake, pocket ported stock heads with blazer springs and 1.5 ratio roller rockers. fair idle cam with .465/.488, 2500 stall converter, th700r4 set up for 450hp with extra hard shifts.
at the moment i have a posi with 3.23 in it.I can't drive it yet because the body is being worked... i have the rear out of it so i was wondering if 3.23's are of any account...i know the tranny had the extra low 1st but will the 3.23's be enough to get good strong acceleration in the higher gears....i haven't driven the car at all since i put the th700r4 in it...thanks if you need any more info just ask oh yeah does the engine sound like it will be strong and work well on the street. some say yes thanks to the porting but want yalls input

angel71rs

Your engine sounds like a good street combination, especially with that stall converter and TH700. I have that tranny in my 89 Formula 350 and 3.27 gears in the diff. Acceleration is great in first gear, but there is a big dropoff in rpm when it shifts to 2nd. Not a big problem with the torque of the TPI 350, but it would run much better if it had closer tranny ratio's and 3.73's. Oh well.

I'm guessing at least 14.2 if you tune the car properly. That means optimizing the engine and doing some suspension work, cause that 3.06 1st gear is a bear. Your car would drop about 4 tenths at the track with 3.73's, if you could get decent traction.

Dirt Reynolds

Looks good to me also. I'll make the assumption that cam is 224 intake and 234 exhaust, duration @.050". Looks to me like the generic Elgin grind (aka Summit, Speed Pro, etc). Should work fine for what you are doing, and be a nice upgrade in power.

That deep 3.06 first gear will get you out of the hole fast.