I am building a 357 for my firebird(350 .040 over) i am going to run 64cc heads, 268xtreme cam hedders, stall converter, etc. i am trying to decide if i want to run flat top pistons or stock dished pistons. with the flat tops i should have about 10-10.5:1 i think, and dished about 9-9.5:1. i dont mind running premium, but dont want to run octane booster all the time. my buddy ran the same engine as i am with stock pistons and he ran 87 donkey **** in it, and it didnt ping. i was wondering what you guys think. thanks for any input.

------------------
Wide Open Till You See God...Then Brake

 

i'd run flat tops and break all the sharp edges on the pistons. i've built several engines with flat tops and the smaller chamber sized heads with no problems with pump gas.

------------------
ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM

 

I'll second ede's advice. 64cc heads on that motor will give you about 10.3 - 10.4, which is about right for that cam. Like he said, smooth all the sharp things in the combustion chamber to help hold down the tendency to detonate, and it will be OK with pump premium.

------------------
"So many Mustangs, so little time..."
ICON Motorsports