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Old 03-03-2013, 06:10 PM
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Get a positive ID on those pistons so you can determine the CCs of the reliefs. That way you can figure your CR.
Porting ....yes...mild.
Clean up inside the bowls (behind the valves) and the runners. Clear any flashing from the port openings and gasket match the openings.
Dont go whole hog in the runners. Hogging them out will not improve street performance.Stock runners perform well with just a smoothing and some short turn radius work . Lower the port floor a little at the short turn radius ...a little. Take a little of the bend out of it.
Any bumps in the runners should be removed. Myheads had some wierd little bumps in a few of the ports. I suspect they were ID marks on the original casting mold to ID them, and the marks just transfered to the part when it was cast. look in there, you will see em.
Keep it simple when porting and dont over do it. When porting , imagine water flowing through the heads and how it would flow better. Air will act similar. Not sure if you can picture that but it was put to me that way, I think I kinda get it.
Fact is stranger than Fiction
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