Quote: so 915 with .040 quench what compression can I run and still use pump regular or premium?
About 9.5:1 with the steel heads.
So is 10.5 good with stealth heads and running 93 pump ??? Yes !
My 440 is stock stroke and .030 over (446) and I use the MP .557 solid cam. I use 906 open chamber heads that have been milled some and I have the KB quench pad pistons. I run right on 10.0 comp and at 37 total timing thats all in by 2000 rpm I have no ping at all with my iron heads. So an aluminum head eng using 11.0 with the right cam wil run fine on 93 pump. At 10.5 on aluminum heads you will be fine. Ron
Ron