Who does Exhaust Manifold Porting? I have a 62 Buick, Some day I will make headers but not anytime soon. Does anyone port Cast Iron porting???
Never heard of that. Makes sense can not see another way to do it. I shall car. Hope its not tooooooooooooooooo $. I a rich retired teacher from a poor rural school in Ohio.
Extrude Hone - Deburring - Polishing - Radiusing, Shaping - Flow Tuning The Extrude Hone process explained - YouTube
I think I wore Greg Gessler out with porting mine. I sure wish someone would do this again. Last thing he did for me was for a 65 LX 425 - intake and exhaust manifolds.
I remember seeing an episode of Horsepower TV several years ago where they ported a pair of (I think Mopar) iron manifolds with muriatic acid.
Getting the whole manifold smooth would me tough. I never thought about how to do it until the other day. I was like "How the hell do you clean down the runners of the manifold?" A Dremel and a camera on a flex tube.
I guess the Acid trick is better then nothing, but it also removes material from the inside curves in the runners. When you only want to do so from the outside wall of curves. If you do not have the porting tools to do it yourself, then the Extrudhone process is the best way to go, in fact it may be THE best way to go even if you are equipped with the tools and knowledge to do it yourself! One things is for sure also, and that is once the work that you have done or the Extrudhone process has done to get the interior of the exh manifolds smooth your going to want to ciramic coat the insides to stop rust from forming again! Here’s why! You might find it interesting that some years ago I spent 3 to 4 minutes on just polishing out all the very ruff rust and carbon build up from a exh port to test the before and after flow numbers. This exh port in the head was about 3 inches long overall. The result from this was that the exh flow picked up 8%! And this was no big effort polishing job that left the port totally cleaned up and shiny by the way! I have whiteness a dyno test where a externally beautiful set of V8 headers had enough rust on there insides to lob 60 HP off of a motor at 6000 rpm!
I contacted a place that used to do extrude hone Pa. He said they don't do it any more and they found coating the insides was more effective.
Not a lot of the "cheater classes" doing extrude honing anymore.. they have gone to straight up grinding with the burrs and stones, as they have perfected the technique to make it look unported. All NHRA cares about anymore is the valve specifics, and port volume. It would be tough to find a Stock Eliminator car that is substantially under the index, that does not have ported heads. JW
