AllC34Me

I have a local gentleman selling a TH400 automatic transmission he had rebuilt then removed from his GTO. I have a TH350 in my 77 Corvette now. I am replacing the engine with the GM Crate 350/290. Three questions:
1) Would it be a good idea to buy and install the TH400 to replace the TH350?
2) How hard a swap might this be when the time comes to do it?
3) Anything I need to watch out for?

Thanks in advance.

David

Gordonm

The 350 is more than capable of handling the motor you have listed. The 400 is a HP robber. It is a great trans and can handle a lot of HP but it also takes a lot of HP to drie. I would stick with the 350 you have if it is in good shape.

AllC34Me

Excellent, thank you. I think I need to pull the TH350 and have it gone over as the car has 85K on it and to my knowledge has never had this serviced. Would the same be true if I used the GM 350HO with 330HP?
Thanks a bunch for your help.
David

Gordonm

The 350 is quite durable and will handle a lot of HP. I would not hesitate to put 500 HP through one that was properly rebuilt. The 400 will just suck up HP

AllC34Me

Thank you.

markdtn

A GTO (Buick-Olds-Pontiac) TH400 has a different bolt pattern than a Chevy engine. You would also have to have a Corvette-specific yoke and change the driveshaft.

AllC34Me

Thank you all for the input. I have passed on the item and instead will seek alternatives. I really appreciate your help.

David