Looking for info on 340 Torker performance mods
Fer what you think it's worth..... EM did a test of gasket matching, and I frankly was surprised how much more hp they claimed. I don't have access to it at the moment, so I've got no more info than that.
As for the oval port intake on a big port chevy head, that is a HUGE mismatch, FAR more than the typical smaller intake that is not port matched. I can believe the bbc mismatch would have an effect on reversion, but not the eighth inch or less on a typical manifold/cyl head mismatch.