looking at the numbers at 97.2 cc chamber. they show to be from a 65 396 325 hp. would these things be worth putting big valves in or run them as is on a 454? if so what would be the cr with standard bore and pistons? 1 valve relief cut on slugs i think. thanks

Somewhere around 9.25 to 9.35 to 1 CR. with .020" thick steel shims, 4 cc valve notch, and piston .025" down in the hole.

A good increase from the terrible about 7.9 to 8.0 to 1 CR. most of the old 454 P/U motors are stock...

AND yes, they will wake up an old 454/468 motor up just fine if you want to add bigger valves and do all the other stuff to them to compliment the bigger valves...

And I grabbed onto a set to play with onna these days too....

pdq67

Not a good head for even a 396. They have the super tight chamber that can give problems adding bigger valves. Try to find the 215 style a much better head.

Right Mike, but like I said, you gotta work them over.... As for shrouding, plunge cut them a schosh to take care of that..

And I am a fan of max. flat quench designed heads even if they are now called "smog dirty"!!

pdq67

pdq67,

"And I am a fan of max. flat quench designed heads even if they are now called "smog dirty"!!"

does that include '66 model 702's?

we ran a set of the 206's in a 468, with 2.25/1.840 valves and an ultradyne solid 288/296
with 11.0 compression. car ran 11.20 at 117 mph
in a 68 chevelle(not my car). with a victor jr, 4.56 and a turbo 400 (4000 stall). nice torque
but they fall off a bit on the big ebnd.

Sure, if the -702's aren't peanut port heads!!

mr68 know's what I'm talking about don't you...

pdq67