Let me know I advised the machine shop I wanted to between 9 and 9.75 but closer to 9.5. We picked out speed pro hyper # H426cp30 -10.5cc . I have 820 heads that will be getting larger valves they are supposed to be 113 cc heads. The machine shop will be decking the block but advised against going to zero deck just in case i need to deck in the future. The heads will get the larger valves, valve job and surface. I am figuring I will be right at 9 to 1 or ever so slightly below. voodoo #60203 as well. going in a 68 chevelle SS, BTO 700r4 2500 stall, rpm intake, SMI Quadrajet, 3.73 rear. Sounds to me like it would be ok Just want your opinions. I just want to be as powerful as possible yet reliable. Thanks again everyone.

is it a 454?

Those pistons have a .100 dome
I run the same ones in my 454 with 101 cc chamber heads.
You will have a nice combo with those heads,cam and pistons
9 to 1 sounds about right

Buying new pistons. Why so low a CR??

I wouldn't settle for less than 9.75 to a schosh under 10 to 1 CR., and that 268 VooDoo cam will love it!!

You are leaving power on the table and you will still be able to run pump gas.

I had ROSS make my 496's pistons at 9.5 w/ stock type .038"/9" composite headgaskets and then I switched to .020" thick shims to up it to right at 9.8 b/c the dreaded, "More power Scotty" bug bit me....

pdq67

You'll be fine with 9 to 1
We ran 13.30's with an 8 to 1 stock 454 with a 238/248 @.050 cam,auto,3.07 gears in a 4000lb. w/driver 69 SS. Even had a ruptured secondary diaphram that we found after the fact.

stick with where you are unless this primarily a race car with some street driving on the side. You'll be able to run a lean cruise mix and a lot of advance to give some mileage, less sensitivity to inevitably lower octane coming in the future, the occasional tank of regular out of the premium pump, keep the plugs clean, etc. IOW, laying off the compression a little cuts you a lot of slack to deal with real world issues that will come up. I don't think anybody is figuring the available gas is going to start turning towards to higher octane.

Thanks again guys. I appreciate the feedback. Yes it is a 454. It will probably see an occasional drag strip run but mostly weekend runs up to sonic and weekend warrior stuff. I feel good about it. Thanks again.