what tranny do i want?
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Joined: May 2007
Posts: 62
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From: scarborough maine
what tranny do i want?
i can no longer stand my th350 which is on my 700 hp big block. By the time i hit 30 mph i am already in 3rd gear, and then when i get to 60 it sounds like i'm drag racing and im sure this is not only annoying but really innefficient. That tranny should NOT be in with that motor correct? I guess i am wondering how painful it would be to switch to a manual with lots or gears. Or maybe a auto with like 5 gears.....is there such a thing? i also heard about clutchless manual but i dont really know what it is. Btw i'm poor- i'll probably buy it used on ebay or something
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Sounds like the tranny is "giving up" from all the HP 'abuse'. 700hp is too much for any standard Corvette auto tranny...and for most standard manual transmissions. You will have to purchase a tranny built up for that kind of power. If it were me, I'd stay with the auto tranny but by an overdrive unit beefed-up for that kind of power.
P.S. After you've done that, the standard differential in your car will be the next thing to go. Your car was never designed to handle that kind of HP/torque. Everything in the drive train [tranny to wheels] needs to be strengthened.
P.S. After you've done that, the standard differential in your car will be the next thing to go. Your car was never designed to handle that kind of HP/torque. Everything in the drive train [tranny to wheels] needs to be strengthened.
Burning Brakes
Joined: Aug 2007
Posts: 1,173
Likes: 1
From: Liberty Missouri
How does someone poor have 700hp….
Try looking at bowtie overdrives (BTO) they can put you in an overdrive for around 2,000 bucks depending what you want and it will be bolt in. I would tend to agree with the other guys sounds like you need to look at you rear end and go to a higher gear.
Try looking at bowtie overdrives (BTO) they can put you in an overdrive for around 2,000 bucks depending what you want and it will be bolt in. I would tend to agree with the other guys sounds like you need to look at you rear end and go to a higher gear.
If I had a 700hp C3 with a bad [auto] tranny, puttin' gas in that thing would make me poor, too! 
Pro
Joined: Nov 2007
Posts: 741
Likes: 1
From: Woodstock GA
If you want an overdrive, beefing any of the more common ones (TH2004R, Th700R4) enough to handle a 700hp engine is going to be expensive. It can be done, though. You might want to look into a 4L80E; it will handle the power (its very similar to a TH400, but electronic), and can be beefed up if needed. You could find one in later GM trucks (not sure exactly which models, probably gas powered and at least 3/4 ton capacity) in a salvage yard. Keep in mind though, that with this transmission you will need an aftermarket controller (computer), and that increases the cost.
For a manual, I would go with a TKO 600 5 speed (Keisler), a T56 (can be upgraded to handle 1000hp), or a Richmond 6 speed. Before ordering any of these transmissions, check your rearend gear ratio to be sure its going to be compatible with your driving style.
For a manual, I would go with a TKO 600 5 speed (Keisler), a T56 (can be upgraded to handle 1000hp), or a Richmond 6 speed. Before ordering any of these transmissions, check your rearend gear ratio to be sure its going to be compatible with your driving style.
