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Old 07-20-2013, 12:29 PM
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Quote:
Originally Posted by Nuck Chorris View Post
This seems a bit much to gasket match, I would have to remove A LOT of material. Also I would have to removed a fair amount of the gasket itself in the middle in order to have it match the head. What should I do?
You are correct- that IS a lot to remove. Unless you're shooting for max flow by doing the whole length of the ports and not just enlarging where the head and intake meet, the best way to go about this is to match the head and intake ports to each other's largest port side. This is port matching as opposed to gasket matching, and is worth the trouble.

Hogging at just the juncture of where the head and intake meet- making a "snake that ate the pig" looking port- will decrease flow due to the turbulence caused by the airflow slowing where the port cross section enlarges.

Very early in my porting I had some success using vaseline on the flanges and gasket, then blowing talc through the ports from both directions. The talc adheres to the surfaces that are hanging in the port, this is used as a template to scribe a rough guide to follow. You can also plot the alignment using machinist blue and a scribe to show the alignment; this is a better, more exact approach. The idea here is to take each side, each top and each bottom of each port to whatever side (head or intake) is largest, and no more. That aligns the ports, and thus the airflow, w/o creating a bulge or an unnecessarily large change in cross section. I've seen tutorials on this, I'm sure you can find one w/a little looking around the 'net.
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