318 head porting for the average joe

VIOLENT\6 said

Running gas on a street driven engine, polishing the intake port can be counter-productive.

A slightly rough surface creates a boundery layer of turbulance & prevents gas from adhering/pooling to the port surfaces.

Polishing the exhaust ports does have benefits.

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Yes, street engine. I have read that the intakes should not be polished smooth for the reasons you mentioned. Probably no smoother than 80 grit? I have also read that the exhaust side can be polished to a mirror finish for optimum evacuation and less chance of carbon build up. This is my first port job, so any advice will be much appreciated. Thanks.