I am looking to replace the exhaust manifolds on my 71. The engine is a 1969 350 block. Would a pair from a 1978 block fit or is there anything to be concerned with. Thanks.

Basically all '70-'81 manifolds were the same, some of the later ones had an EFE valve, all had the option of smog tubes.

The difference is:

http://extranet.enginequest.com/images/ex1466.jpg
and
http://extranet.enginequest.com/images/ex1350.jpg

Gm started putting in the brace due to the early ones starting to crack when they got hot.

No, I figure GM started putting braces on them when they started curling/shrinking to where you couldn't bolt them back on after removing them!!

I wouldn't a believed it if I hadn't tried to R&R one that was shrunk so bad the bolts wouldn't go back into the block!!!!!!!

pdq67

Anyone have a spare set of manifolds in good condition they want to get rid of.

I got a rust-ass pair I'd love to throw out.. I mean... sell to you... for the price of a good set >.<

!!!! I hope I don't find that mine are too warped to reinstall after just paying to have them polished inside and ceramic coated!!! lol May never get rid of this dunce cap!