do i have to much compression for the 268 xe. specs 454 -20 over 702 heads cut 10 deck cut 10 stock valves.

Dunno, what's your compression? Flat top pistons, how far down the hole are the pistons, what's the chamber size, what gasket you using?

flat tops-steel shim -15in the hole- 97cc-702.

You are at a .035" quench and I "think" you should be up at 9.75-9.8 CR. w/ stock type flat-top pistons. If so, you are good to go and I figure anything up to 10 to 1 w/ an XE268 cam is fine on good pump gas nowadays, imho.

My 'puter's screwed up or I'd run it here for you.

http://www.campbellenterprises.com/Race%20math%20calculators.htm

I wanna say w/ those heads stock, w/ .020" thick stock type shims and flat-tops, you'd be at 9.3 or so CR.

Please run the numbers and post back how far off I am?

Thanks and waiting.

pdq67

PS., I have a bare set of -206's out in the garage.

Running the numbers on the campbell calc., I got 9.67 to 1 compression. I went with -3 cc's (dish, but not really) figuring that the pistons have the little valve reliefs.

I figure you're good with the 268 cam, probably have to run premium though.

Thanks Brad,

I wasn't off all that much after all.

268 cam, the sucker should be powerful in the midrange, imho..

pdq67

thanks . just installed the xe268......