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Old 04-08-2014, 08:01 AM
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88nightrider 88nightrider is offline
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Originally Posted by AMMFAB View Post
the only thing that doing a mirror finish on combo chambers or exhaust would help to do is the slowing of carbon build up over time. which i dont think these things go for long enough to ever build up enough carbon to start to effect air flow.... but i could be wrong
I know this is an old thread.
But just to add to this. Polishing the exhaust port to a "mirror" finish also helps on cooling.
A flat surface has less surface area then one that is rough. So less material is in contact with the hot exhaust gasses to soak up the heat. While the "mirror" finish also reflects some of the heat

Originally Posted by AMMFAB View Post
what u dont want in a ported head especially on theses little carburated engines is a mirror smooth finish (intake port). which alot of people think is what u want and they are wrong. if u notice i have a bit of a texture on the ports walls and thats on purpose. it helps the fuel to stay atomized as it enters the engine instead of "falling out of vortex and pooling" some people say
This is absolutely right
You can clean up your intake port to smoothen it up a bit, while still leaving a bit of texture.
Some of the same as with the exhaust port applies here (just the other way around). By having less texture there are less time for the intake charge to pick up heat while entering the cylinder.
But balancing this might not be so easy...