Port matching heads to headers

The flanges on the headers should be made to match the gaskets, which match the heads.

IF you have selected a camshaft that maximizes the flow characteristics of the ports, then match the gaskets on the exhausts.

IF instead you have selected a "sane" street cam, then don't bother.

It's far more important on the exhaust to match the size of the tube to the flow of the exhaust port.

If the flow numbers on the heads show say 330 at .630, 220 on the exhaust and you put in a hydraulic lifter cam that is .580 lift, again, don't bother. No matter what you do, the heads aren't working anyway.

It's pretty difficult to maximize the flow of the headers at the flanges. All sorts of compromises had to be made just to attach the tubes. Many turn the wrong way or the radius is too tight, etc.

Even if the builder got some of them right, usually half of them are wrong.

Matching the gaskets? "Much ado about nothing". Save the money.

FWIW, Larry- I agree with Doug. Head and intake manufacturers do the best they can on port sizes and orientation, using dyno runs and all when building their products. Then hot-rodders with die-grinders promptly alter the ports to match someone's stamped gaskets! Note also that gasket openings vary noticably from different sources. All I usually do is make sure the header flanges are flat, as welding distorts the finished product.

Found these guys make header flanges. I've no other info on it.

http://www.spdexhaust.com/pdfs...anges/351C-M-400.pdf

quote:

Originally posted by Bosswrench:
FWIW, Larry- I agree with Doug. Head and intake manufacturers do the best they can on port sizes and orientation, using dyno runs and all when building their products. Then hot-rodders with die-grinders promptly alter the ports to match someone's stamped gaskets! Note also that gasket openings vary noticably from different sources. All I usually do is make sure the header flanges are flat, as welding distorts the finished product.

I'd recommend using the Fel-pro header gaskets.
These are for the aftermarket aluminum heads. My header flanges match these.

I used Remflex solid graphic #RF3006. They are a bit over 1/8" thick and sealed great on my Edelbrock aluminum heads. My header flange was not perfectly flat and these sealed the leak, been on for years. I have a previous post with a picture.

quote:

Remflex solid graphic #RF3006

Summit link

That particular gasket is for the iron 4v heads. The Edelbrock takes the gasket I posted.

It is made out of graphite, not graphic, whatever that might be?

good one Doug