Thread: High port head cross section of ports. (RWD SR20DET)

Found this on the HeadGames Motorworks web site.
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Lets go in on an bandsaw Ben so we can do this to your old head.

How do the valves stay in? ha ha...

Thats pretty cool.

Why does the exhaust port pinch like that?

I assume they cut the head and didn't go through the center of the exhaust port. It looks like the cut went down the center-line of the intake port for the most part but ended up veering off and went down the side of the exhaust port really skimming the side of it at the end. Maybe the cut is straight and the exhaust ports aren't straight themselves.

That would scare customers into paying for major port jobs, if it's not centered...

Maybe it is centered and it necks down to prevent reversion? I know there's a little step to help prevent reversion, but I don't think it's nearly that big. =]

Don't forget there are actually 2 of each valve and the pic only shows the cut through the back pair of valves. The 2 separate exhaust ports merge together to form one hole at the manifold interface. You're seeing where the back of the rear value's port turns forward towards the single exhaust port.

Of course. Should have spotted that.

that really shows ya how much room you have when porting, well on that cylinder anyway.. would be cool if they made it into 1/4s