In the "Big Bolts" forum, post titled "53 6400 Gets a 261", .... I responded to the post & believe it should be brought here to this forum. Anyone hip on porting & polishing for this engine, please shed some light on it. Here was my response/ question in that thread:
Interesting that "polished out carb" was brought up. With bikes (Harley) some ppl believe that when the heads are polished inside, that cfm is gained which translates into more horsepower. According to "Perry Kime" a coarse surface is best for air/fuel atomization. Atomization won't happen as well in a smooth surface.
Basically his set ups go from rough finish in the intake manifold, then at some point in the heads, the surface gradually gets smoother to the valve seats. Then the valve area & the exhaust ports are highly polished out. He referes to this entire process as a "tool finish".
This leads to the question, how can/ does this get done on different GM engines?
