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:confused: ok so ive ben researching info on porting and polishing my heads........................i found some info that lead my to beleive that intake ports need that rough textuer to prpperly itemize air and fuel any porting you do is going to virtualy eliminate that " needed" surface!! so whats right fellas help me out here ive all ready smoothed the exaust ( didnt spend too much time there) but want to move to the real stuff!! i know some 0f you guys out there are experts!- thanks dudes:confused:


-joey
 

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On the exhaust side you would want the smoothest finish possible to help get the exhaust out with no obstructions as quick as possible. On the intake side, I normally smooth the transitions in the runners and the short side radius, and parting lines. but leave a rather rough finish in order to promote some turbulance. I have been told that too smooth of a finish will cause the fuel to come out of suspension and pool in the runners. Whether its tru or not I don't know. either way I leave a a 120 grit roller finish.
 

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The real gains in porting have very little, if anything to do with how the surface is finished. If you just sanded the exhaust ports, without knowing where and how to radius in the bowls, you likely didn't help, or hurt anything. You need to know the correct areas to grind, and the areas NOT to grind. The best job a novice can hope for is to just blend the bowls, and gasket match the intake. Again, if you don't know how much is too much when blending the bowls into the seats(how much radius to leave in there), you can easily hurt low and mid lift flow. Just try to make a nice rounded radius leading into the seat/bottom cut and you should be ok. Just smooth and blend the short turns without removing much from them. As for the finish, I finish the intakes with 60 or 40 grit, exhausts with at least 120 or finer 240, depending on how much time I want to spend. Peel the rolls out a little to make a "flapper" to finish it out. The finish is really for the customer to ooh and ahh over when he pays good money for the work. JMHO.
 
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