Hi, another question from my visit with Jim at the machine shop.
As a backdrop, I'm looking for nice performance gain but no plans to race. I'd been planning on a lump-port head, because it seems the thing to do.
Jim thinks that a street machine with headers could use popping up valves one size is all that I need and that I don't need to go the path of lump porting. I don't recall now if he said intake or exhaust or both, but he said something like going from 172 to 182 but not 192. Other guys who work on a variety of older Chevy's, including the president of the local Camaro club, dislike modifications and believe that messing with original is either not necessary or asking for trouble. I think experience shows modifications work out fine if done right.
Jim also prefers to use studs in the engine with bolts to allow for higher torque reducing the risk of head warpage. Thinking about this after the fact, perhaps the studs change to a finer pitch on the nuts to allow tighter torqueing.
Of course, lumps are incompatible with stud bolts.
Since it's time to put up or shut up, what are your thoughts?
Is this a silly question to ask in this forum where everybody lump ports? Should I take this as a hint?
Thanks!
Mark
