My 307 rebuild... yes a 307

[Chuck78]

The vortec combustion chamber design (shared with the LS1 and fastburn also I believe) is hands down proven to be the most efficient combustion chamber that GM has ever made on a V8, so I'm sure the vortec will get far better milege than the old 307 heads. I think I recall someone stating that they flow better at a street rpm range than the fabled camel hump/double hump heads, which have 2.02 intake valves even compared to the 1.94 vortecs, and they also get much better gas mileage than those.

With gas prices creeping back up, I am really wishing that I had kept that old 307 for such an occasion!

One side note, at the time I had it, I was considering doing an oddball 307 with a longer stroke and 5.7 rods, and I actually found an AMC piston that had a very similar bore and was the correct pin location and piston height to use a longer stroke sbc crank. You couldn't have bored the 307 out .020 or 030, it would have been like .033 or something close (would have been .020 or something for the AMC engine). I browsed a manufacturer's entire catalog of pistons to find that. I think it was a 6 cylinder. It would have worked out to about a 332 or 334 cid I think?