[Skip Fix]

Many guys post here their car is running fine on pump gas my RAIV had a moderate amount of overlap also. I'd bet a dyno test with race gas they would see a need for more octane.

Dish options-custom from Ken etc, in whatever size you want. KB hypereutectic-be sure to gap the top ring EXACTLYto thier specs or break ring lands., Get a F-M(TRW) forged 2262 machine a 2.8x0.100 dish on the lathe -the old HO dished Ken Crocie used to sell., I think that figures around a 9.9cc dish. Bet by the time you add the machine work Ken can get you a better deal.

Other option is opening the 670s chamber closer to a later 68 and up chambers. Tom Wilhite has a special Bridgeport cutter for this. That should get you the 10cc easy if you don't need a fresh rebuild. I always thought opening them to copy a late model Fast Burn SBC chamber(biased toward the exhaust) and keeping some of the quench would be a good thing to try on 670s and drop the compression.

[JKrull66]

[QUOTE=Skip Fix]

Other option is opening the 670s chamber closer to a later 68 and up chambers. Tom Wilhite has a special Bridgeport cutter for this. That should get you the 10cc easy if you don't need a fresh rebuild. ()()()()

I have heard of this process, I have a set of 670's that I would like to have this done. Can the process be done on heads that are assembled or at least already have guides. Do you have any more info, Location, Cost, Contact info, Web site ?
Thanks JK