Hey I was wondering what kind of tranny to get I just bought a 1989 z28 with a 350, holley 174 supercharger, and a 275hp wet shot of nos. the tranny blew about 2 weeks ago and nobody around town can help me out.

 

do you want a manual or an auto?

 

The 275 is a pretty big shot. If it weren't for that I'd say a built 700-R4 or a T-56 with steel forks and a good clutch would hold it, but if you're gonna spray that hard you need either a built TH350 or a TH400.

Also, you better pray that whoever put that blower and bottle on it also went with a forged bottom end, because if it's a stock rotating assembly it won't last long.

Also the 10-bolt won't hold up to that kind of power....save for a 12-bolt or 9".

Also if you don't have subframe connectors get some before the torque twists your unibody apart.

 

what options would you have if you wanted a manual but needed something a fair bit stronger then an lt1 t-56?

 

Lenco, Jerico

 

The T-56 can be strengthened a bit with cryo'd shafts and crazy stuff like that but it's incredibly expensive.

 

on average how much power would you feel safe running through something like a richmond 6 speed?

 

Turbo 350- cheap and strong.

 

I personally don't know enough about the Richmond 6-speed to make an estimate.

I'd feel safe up to around 550-600hp on a stock T-56, and probably 750 with steel forks and kevlar synchros and a decent clutch and such.

G-force builds a 5-speed that's rated at like 1000hp, but I think the price tag is in the 4-5 grand range.

 

I agree with J. I wouldn't be afraid to say the Richmond could hold a couple hundred more.

By the time I got over 750hp, the thing would be a pure track car though so I might go auto anyway...

-Rippin

 

well thats my dilemma basically. I am hoping to have the majority of the work i want to do done in the next 5 years ?(im only 17 right now) So what i wanted to do when i did my engine was have a bullet proof short block even though ill only be putting out 400-500 hp i dont want to rule out slapping on a massive turbo/supercharger to put a massive bump in my hp. Except for when my car becomes a "pure track car" that track is going to be a race track not a drag strip so i need a manual. Im thinking ill end up with an lt1 t-56 and then when im getting ready to slap on some forced induction save up for a jerico.

 

Sounds good. Jerico's are nice... I agree with you about the "racetrack" as compared to drag strip. If it was me, no doubt it would be a road course car, I just assumed you were looking to have a drag car Have you had your car on a road course yet? I can't even imagine. I'm hoping to go to Road Atlanta soon, that would be such a blast!

-Rippin

 

Rippin if you ever go let me know...I might just meet ya there.


I think 750+hp would be a bit much for a road track. You'd have too much trouble holding the rear tires planted when accelerating out of a turn, and the extra weight from the beefy trans and other "support" items would be a drawback. If I ever put mine on road-track duty, I want a low-boost blower on my 355 (say about 5psi to make roughly 450-500hp.) That's plenty of power to make time on the straights, but not enough to require a heavy Jerico and a power-eating 9" rear. I could run the T-56/9-bolt setup I have now and be just fine.

750+ is straight-line-only range. That calls for an automatic trans.

 

auto = th400
manual = t-56
If your car ends up with 600+ with the spray, get upgraded parts for the t-56... "taner" from this board runs a 9.6@141.5 with 630rwhp and it says on his site and BMR's that he has a stock t-56
http://www.bmrfabrication.com/FeatureCars/Tanner.htm