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Discussion Starter · #1 · (Edited)
I have a 1978 Corvette L-82, and I would much rather have a 4 speed tranny than the stock automatic. Im looking to upgrade horsepower later on too, and ive heard the Muncie 4 speed might not be able to handle much more than 250-300hp. What other 4 speed transmissions can be used for this car? Also, any other helpful tips or ideas would be appreciated.
 

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Munci can handlea good deal more than that , but have you considered the benefits of going to a 5 speed trans instead? There are several available and even some used ones around . someone recently posted they had the entire clutch set-up , bellhsg,5sp trans and all for around $800.
 

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i would use the tried and true super t-10, since that was what came in trans ams/corvettes anyway.....should be good for 450 plus hp provided no slicks and no 5000rpm clutch drops.....
 

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I like the Tremec 5 speed.

http://www.smokinvette.com/corvetteforum/showthread.php?t=13261&highlight=grand

You will need to be sure the find out if you need to change the cross member. I was told a while back the you could not just drop in a 4 speed in an early C3 if your car came with automatic.

because the crossmember is welded on manual cars ,it hard to go to auto trans,but if you have auto trans with bolt on crossmember ,you have no problem installing manual trans.
 

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Discussion Starter · #7 ·
Thanks And Keep Replying!

I have actually thought about a 5 speed.. but i like the acceleration a 4 speed gives you vs a 5 speed adding a little more top end. I looked at two Tremecs and a Richmond OD. If a Muncie could handle say.. about 375-400 i would be okay with that. If I advance past 400HP I would consider upgrading the tranny again. Any other tips would be appreciated still!
 

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I have actually thought about a 5 speed.. but i like the acceleration a 4 speed gives you vs a 5 speed adding a little more top end. I looked at two Tremecs and a Richmond OD. If a Muncie could handle say.. about 375-400 i would be okay with that. If I advance past 400HP I would consider upgrading the tranny again. Any other tips would be appreciated still!
you can get Richmond 5spd with lower 1st and 2nd gear making much better low end. and Munci can handle 400 HP easily. Gm used them in 454 Corvettes for years with no problems. You won t hurt it
 

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little bro is running a super t-10 behind a full-roller 468 making upwards of 550hp in his 67 camaro, 4:10 gear and 3660lbs in full street trim. hasnt broke....YET. but again, no slicks and no 5000rpm clutch drops makes it liveable....tell ya what tho, those 15x10 welds with 275/60/15 BFG radial t/a's get a WORKOUT--rubber in all 4 gears no problem, and he's a granny shifter. thats also why it lives, no 'speed shifts'....
 

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the Borg Warner super t-10 is a tough trans, but Munci s are pretty good too,I had several, one in a 69 vette 427/430 hp. It had about 200,000 miles on it and never failed once . leaked a little oil ,and I drove the **** out of it
 

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Discussion Starter · #11 ·
Did More Research

Looked over the ratios for the Richmond OD again. 1st: 3.33 2nd: 2.89 OR 1.85 3rd: 1.31 4th: 1.00 5th: .77. The only concern i see now that i looked back over it is the drop from 2nd to 3rd if i were to get the 2.89 ratio option for 2nd. What would the results be with that big of a drop from gear to gear? And woud it be bad for the engine/trans?
 

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unless you are building a "bad ***" motor for it too, I think you ll be pretty satisfied with it. I have 700R4 in 81, 1st is 3.o6 and 2nd is 1.83,and its fine with my stroker motor. you ll have better power to launch, and thats where it counts. neither one will hurt anything unless you plan on slicks and dropping the clutch at 5500rpm
 
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