TH400 Discussion

[patmckinneyracing]

I'm trying to make a list of parts and learn more about the TH400. It is not for me, but for my uncle who plans on using it in his t-bucket style dragster (forgot the name but some of you may know what I'm talking about). He'll be running a 454 making 400hp, he is not mechanically inclined but I think he could easily be making more than that. Plans on running a 3500 stall with a chevy 12 bolt in the back. This thing is only going to see 1/8 and 1/4 mile passes, no street use.

So far I have no idea what he has put into the motor, camshaft or anything, and neither does he...pretty scary if you ask me. He's one of those that has that "showcase" personality. Supposedly the builder, who also helped me build my motor 5 years ago, told him it would make approximately 400hp.

So what I need to know is what are some trouble spots with this transmission? I know these are one of the strongest transmissions out there and can probably handle 400hp easily. But I'd rather give my uncle a list of good parts that will make this transmission bullet proof behind this 454. Think a good goal is to build it to 550hp specs for safety sake. Should he go with a standard rebuild kit, alto clutches, or what? I just got done with my 700r4 and know more about it than the 400 so any help is much appreciated.

 

[RegalBegal]

The TH400 will easily live in stock form at that HP level. Tell him to pick up a Trans Go shift kit. It comes with some high durability parts to install during a rebuild (retaining rings, clutch pack spring, etc). The biggest thing, as with all automatics, is KEEP IT COOL. Use Alto or Borg Warner clutches and opt for Kevlar bands. Make sure the rebuild kit comes with steels!

 

[Blake442]

With the weight of a T-bucket, He could probably get away with a TH-350 or PowerGlide that would rob less power.

Theoretically, He could just use a stock-ish 400 with a nice shift-kit and a good external cooler and be just fine.

Otherwise just tell him to open up the Jegs catalog and order a bullet-proof one from TCI for about $800.

 

[patmckinneyracing]

That's what I figured. I wish I knew what he had put in that motor so I could actually go into detail a little better. I've never had a problem with Transgo shift kits either and they have always been good.

Blake, I thought about the TH350 since mine is holding up behind my 350 making roughly the same hp, not torque of course. I figured TH400 in case he gets a wild hair later and rebuilds the 454 or it makes more power than predicted.

 

[JBreu]

With the weight of a T-bucket, He could probably get away with a TH-350 or PowerGlide that would rob less power.

Theoretically, He could just use a stock-ish 400 with a nice shift-kit and a good external cooler and be just fine.

Otherwise just tell him to open up the Jegs catalog and order a bullet-proof one from TCI for about $800.

x2