). Thanks!
TH400 swap
Thread Starter
Melting Slicks
Joined: Mar 2004
Posts: 3,472
Likes: 18
From: Lake Ozark, MO
TH400 swap
Is the TH400 a direct swap for the 350? By direct swap, I mean transmission length and bolt up to existing 350 frame pieces....understand that some of the linkage may need to be relocated or reworked. Car is a 78.
Race Director
Joined: Sep 2002
Posts: 10,362
Likes: 5
From: San Diego - Deep Within The State of CONFUSION!
Originally Posted by Hvymtlc5
Is the TH400 a direct swap for the 350? By direct swap, I mean transmission length and bolt up to existing 350 frame pieces....understand that some of the linkage may need to be relocated or reworked. Car is a 78.
Careful - there's two Turbo 400's (long and short tailshaft) I had to look a lot to get a short tail section but there's a lot of them around nowadays.
Rear yoke is different and the mount is diff too, so you'll need a new crossmember.
A built 400 can handle a lot of power. After literally grenading planetaries in my Turbo 350 twice with that Nova, I drove it for 5 years afterwards with a Turbo 400.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
What is so wrong with a 350??? Built they can handle alot of power. Unless you are a serious racer just have the 350 built. They actually respond better then a 400 to a shift kit.
A 400 also eats about 35 more horse then a 350.
I know for all out racing/toughness a 400 is stronger but for the street the 350 with a shift kit is a very good transmission.
A 400 also eats about 35 more horse then a 350.
I know for all out racing/toughness a 400 is stronger but for the street the 350 with a shift kit is a very good transmission.
Instructor
Joined: Dec 2004
Posts: 236
Likes: 0
From: Clearwater Florida
Here is a Link that may answer some of your questions.
http://www.tciauto.com/tech_info/trans_dims.htm
Although not a corvette, I recently swapped in a TH400 where a TH350 used to be in a 86 full size Silverado.
Besides the drive shaft length issue you will need to get a slip yoke that fits onto the TH400 tailshaft. The TH350 slip yoke won't fit on the TH400 talshaft.
Also keep in mind that Chevrolet always installed the TH400 behind big blocks from the factory. As far as I know you could not buy a big block equipped car or truck with a TH350 installed from the factory.
http://www.tciauto.com/tech_info/trans_dims.htm
Although not a corvette, I recently swapped in a TH400 where a TH350 used to be in a 86 full size Silverado.
Besides the drive shaft length issue you will need to get a slip yoke that fits onto the TH400 tailshaft. The TH350 slip yoke won't fit on the TH400 talshaft.
Also keep in mind that Chevrolet always installed the TH400 behind big blocks from the factory. As far as I know you could not buy a big block equipped car or truck with a TH350 installed from the factory.
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