TH400 weak links
UncleBob
03-05-2006, 02:32 PM
When building a turbo 400 tranny for dealing with 800-1000HP, what modifications/parts are crucial?
I'm not much of a tranny guy, I'm trying to get an idea of what level is realistic.....is this a situation where I'd be better off building a powerglide for good longevity? I'd rather not use a powerglide if I can avoid it.
I'm not much of a tranny guy, I'm trying to get an idea of what level is realistic.....is this a situation where I'd be better off building a powerglide for good longevity? I'd rather not use a powerglide if I can avoid it.
MrPbody
03-07-2006, 07:42 AM
Bob,
The usual modifications include an aftermarket "heavy duty" sprag (one-way clutch), 6-clutch drum (forward drum) and a good shift kit. We recommend TransGo for TH400. If it's a race car, a "reverse" valve body is called for (reverses the shift pattern for the forward gears). A trans-brake is another option. What kind of racing will it see?
In a lighter car, PowerGlide has an "edge". In a heavier car (over 2,600 lbs.), TH400 with a bit taller rear gear is called for.
Jim
The usual modifications include an aftermarket "heavy duty" sprag (one-way clutch), 6-clutch drum (forward drum) and a good shift kit. We recommend TransGo for TH400. If it's a race car, a "reverse" valve body is called for (reverses the shift pattern for the forward gears). A trans-brake is another option. What kind of racing will it see?
In a lighter car, PowerGlide has an "edge". In a heavier car (over 2,600 lbs.), TH400 with a bit taller rear gear is called for.
Jim
UncleBob
03-10-2006, 12:36 AM
Bob,
The usual modifications include an aftermarket "heavy duty" sprag (one-way clutch), 6-clutch drum (forward drum) and a good shift kit. We recommend TransGo for TH400. If it's a race car, a "reverse" valve body is called for (reverses the shift pattern for the forward gears). A trans-brake is another option. What kind of racing will it see?
In a lighter car, PowerGlide has an "edge". In a heavier car (over 2,600 lbs.), TH400 with a bit taller rear gear is called for.
Jim
it would be street/drag racing car, and it would be heavier than 2600#, more like 3200. But it will be a turbo'd engine, so taller gearing is quite OK.
Its as always a question of how much is street and how much is strip. but thats purely performance, I'm just trying to find out if the TH400 could handle the abuse
The usual modifications include an aftermarket "heavy duty" sprag (one-way clutch), 6-clutch drum (forward drum) and a good shift kit. We recommend TransGo for TH400. If it's a race car, a "reverse" valve body is called for (reverses the shift pattern for the forward gears). A trans-brake is another option. What kind of racing will it see?
In a lighter car, PowerGlide has an "edge". In a heavier car (over 2,600 lbs.), TH400 with a bit taller rear gear is called for.
Jim
it would be street/drag racing car, and it would be heavier than 2600#, more like 3200. But it will be a turbo'd engine, so taller gearing is quite OK.
Its as always a question of how much is street and how much is strip. but thats purely performance, I'm just trying to find out if the TH400 could handle the abuse
MrPbody
03-10-2006, 07:53 AM
Bob,
You'll get other opinions, but mine is that TH400 is absolutely the best 3-speed automatic ever made by anyone. It's every bit as tough as C-6 or 727, and has a more "sophisticated" power flow and shift process. It's the MOST popular (3-speed) in drag racing for many reasons.
If your budget can stand it, companies like TCI and ATI build 400s guarenteed to stand up to 1,500-plus horsepower. Just how big a "turbo'd" are you building?
Jim
You'll get other opinions, but mine is that TH400 is absolutely the best 3-speed automatic ever made by anyone. It's every bit as tough as C-6 or 727, and has a more "sophisticated" power flow and shift process. It's the MOST popular (3-speed) in drag racing for many reasons.
If your budget can stand it, companies like TCI and ATI build 400s guarenteed to stand up to 1,500-plus horsepower. Just how big a "turbo'd" are you building?
Jim
UncleBob
03-11-2006, 01:15 AM
Just how big a "turbo'd" are you building?
Jim
as big as I can for as little money as possible :lol:
But I don't want to do the revolving-door on trannies either.
How much do the insane-HP-capable prepped 400's go for? I assume they aren't cheap....
Jim
as big as I can for as little money as possible :lol:
But I don't want to do the revolving-door on trannies either.
How much do the insane-HP-capable prepped 400's go for? I assume they aren't cheap....
MrPbody
03-13-2006, 08:02 AM
Bob,
I can't say for sure. Upwards of $2,000, I would guess. I would contact TCI first. They have the high-end covered.
Jim
I can't say for sure. Upwards of $2,000, I would guess. I would contact TCI first. They have the high-end covered.
Jim
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