Will a Buick TH400 bolt up to a SBC?

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If it's one of the universal trannies that GM built.
Usually in the mid 80's cars like this one.

th350C_unicase.jpg

Speedway sells this adapter for $39.99
I've used it several times and it works great.
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If it's one of the universal trannies that GM built.
Usually in the mid 80's cars like this one.

Iron, didn't see the adapter first time I saw your post! Thanks, that's what I'm going to use!

Zipper
 
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the trans will line up with the dowels and bolt up with 2 bolts other then that no. i have never seen a dual pattern th400, not saying they don't make one just i never seen one.
 
the trans will line up with the dowels and bolt up with 2 bolts other then that no. i have never seen a dual pattern th400, not saying they don't make one just i never seen one.
Yea I was locked in on a TH350 didn't read well enough.
The adapter will work with any GM tranny.
 
Nailhead ??

Nailhead buicks used the TH , But the nailheads trans has a shorter belhousing part of the case. Nailheads have an extended bell as part of the engine block. and buick nailheads found they way into Jags, rolls and other euro cars.
 
I think you are thinking about the so called "baby nailhead", the aluminum block 215 V8. The tooling for it was indeed sold to Rover in England and with a few changes used for years in their vehicles. Don't think Jag ever used it, or Rolls, they had their own engines. It wasn't really in the nailhead family, but it was a similar design and might have shared a few parts, but not many.

I think the only TH used on the real nailhead was the TH 400. Don't think they ever got the TH 350. I've never ran across a TH 400 with a BOP {BUICK, OLDS, PONTIAC} and Chevy pattern both, but they may have made them and I just never saw one. I have seen the TH 350 dual pattern ones however. I think they came about in the late 70's-early 80's when GM was doing away with branded engines, They used up what supply they had built then started putting "corporate" engines in, which was the small block Chevy. My Grandma had a Buick with a Chevy 350 in it. By changing the trans and going to the dual pattern, they didn't have to keep making transmissions to match the other bolt patterns, BOP in particular. For a while, you still had the option on the branded engine or the corporate engine, but it wasn't widely known or advertised, and when some owners found out their Buicks and Pontiacs had Chevy engines, they sued GM for some big bucks.
 
Nailhead Th

We have a non running Jag in the driveway that is donor for the suspension for my step son's rat 46 chevy pickup . The Jag has the th 400 or sometimes called sp 400. I haven't decided if I will use it behind my 401 that has the dyna behind it right now. ony a few years nailers used the th 400.
 
The sp400 has the variable pitch converter. Put one in my 53 Chevy with 500 caddy engine had to find a bop tranny case that had to be early 70 to work
 
If i remember right the bop th350 and th400 will not bolt up behind a nailhead. a adaptor is made but it uses a chevrolet trans in that setup. Cost too much for my projects.
 

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