Thread: 454 Headers

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My exhaust ports on my 1985 Chevy 454 are Approx. 2.0 X 2.0 square. I am having trouble finding square flange headers. Can I use round flange headers or will there be too much restriction ?

Naces

What are the heads off of? Check with Hooker, a lot of thier headears are square at the flanges, or you could call Summit.

you can rework the header flange with a die grinder and blend it a bit if a 3/8 thick flange. sounds like some ported them out to big?. to run a round tube you would need a 2 3/8 tube with out any restriction with out any work what are you doing with them heads how big of a engine street strip what ??

The engine is a stock 454 but the truck came out of California at one time. The heads are injection heads with ports of about 1.96 X 1.96 with rounded corners. I will be running this engine mostly stock right now in my 85 3/4 ton untill I get my 70 chevy stepside done.
Thanks

Are they the "Peanut port" intake port truck heads (i.e very small). If they are, the header shouldn't be a problem.

you need to look at the radius take some thing round will tell you how big you need to be with out a restriction sound like a stock port any 1 7/8 to 2.000 header will work the ex side of port is not smaller on the peanut ports ex side .it is on the intake side