Best Valve Size For Power/Durability

SLCK64 · Jan 13, 2008

I am building a 68 302 for my 64 Merc Comet and was wanting to step up intake and exhaust valve sizes and was wondering..... What i the biggest valve I can go and not have to worry about head damage of some sort. I wanna put a pretty decent sized cam in it and I am looking to go to the strip maybe a few times a month but mostly make it a daily driver for the good months of N. IL weather, so I dont wanna push the limits of catastrophic failure after a couple of years. Or should I just get a good 3-angle valve job(best angles?) and leave them stock size? Thanks for your help!

dc-dd · Jan 13, 2008

Are you using stock heads ??? If so think again get your self a set of new heads there are many makes that are fairly priced and you do not have to go aluminum if your on a tight budget. They will be a better product and you will gain more horespower.

Dominic

roddster · Jan 13, 2008

For instance. The late (not sure of the year) Explorer seems to have iron GT 40 heads. And you could probably find them in a U-pick yard.
Unless it is positively necessary to reuse the original heads, you might want to look further in that.

By the way, I see you say you live in Northern Illinois. Look us up on the VMF. www.Vintage-Mustang.com The "we" I mean is the Chicago V-M guys. Yeah, no charge, just a look conglomerate of Mustang owners from the Chicago area. And, you can probably get you headwork/modification questions answered there too.