Originally posted by Big Blocks Rock
I have an add on question. I plan on working a Dodge 383 with MPI for the future, I'm planning on welding bungs onto a Edlebrock single plane manifold and matching it to a set of Edlebrock heads. I want to see if I can port the heads myself and I will match the heads and intake to the gasket. Question is, would I get any performance out of porting and polishing the single plane? I would think that it would. Most of the plenum will just be air, so I wont need the vaporization effect in that area. Oh almost forgot, I am looking at turbocharging it also. I feel that the smooth surface should help in the plenum, especially for the fact that it will be a positive charge. Any comments?
I don't understand your statement "Most of the plenum will just be air, . . . .". Hopefully the plenum will be filled with a perfect mix of air/gasoline so the vaporization requirement will be the same as any other manifold. Smooth isn't necessarily desirable in intake manifolds. The turbulence caused by rough surfaces is useful in mixing and vaporizing the air/fuel mixture. If your car is a race car running @ 3000rpm and up, by all means get the single plane. However, if you want to do any amount of street driving, stick with the perfomace dual plane design.
On this subject, does anyone know if someone is still offering the 'extrusion' process where they force a paste loaded with carbide grit through a manifold, thus opening up the passages? It was hyped in the rod magazines for a time in the 90s and I have heard zero about it since.