maximum compression

[GoMangoBoys]

We are going to run 906 heads on our 383 stroker (either 432 or 489).  What is the maximum compression we should build for in order to stick with pump gas?  I know these are not as good as the aluminum or the closed chamber heads in regards to quench, but I got a good deal on them and I am trying to control cost.
Thanks

[1 Wild R/T]

9.5ish is about the max

[HP2]

Keith Black makes some decent quench dome pistons with reasonable compression ratios for standard stroke cranks. I haven't looked at them lately, but with the proliferation of strokers, I bet they are keeping up with that demand too.

I typically don't build to a set ratio but try to achieve a cylinder pressure of around 180 psi for pump gas. Figuring out cylinder pressure is tougher to do as doing so can also takes into account altitude and camshaft event timing.  However, doing this can also allow you to maximize the compression and best utilize  what you have. Depending on the cam you are thinking of using, that 9.5:1 ratio could perform like a 7:1 which is why, IMO, its worth considering valve events to chose compression ratio.

One I've used for a long time is here:
https://www.rbracing-rsr.com/comprAdvHD.htm

[Chryco Psycho]

Cam profile is a big factor , I have seen 7:1 motors ping badly & 10 ;1 not ping , quench is very important

[Cudamike]

I have Stage V heads at 9.9:1 with 93 octane.