I stopped by my machinist today. He's been pretty busy lately but my block should be done within a week. I didn't have a lot of time to talk to him. So I have a few questions...

I have a 350, 2 bolt main block, casting number 3970010. It's going to be bored .040" over. The deck height is 9.010". Speed Pro hypereutectic 10cc dished pistons (pt# ZWH423NP40) come with the rotating assembly I'm going to order.

According to Keith Blacks compression calculator with-
67cc combustion chamber (Summit Racing Iron Vortec Heads)
10cc piston dish
.038" thick head gasket
4.040" cylinder bore
4.080" gasket bore
5.7" rods

My static compression is 9.382:1

My dynamic compression is either 7.077 (smaller cam) or 7.202 (larger cam) depending on which of the two cams I'm looking at.

Obviously both the static and dynamic compression ratio's will change if the head gasket thickness and/or bore diameter are changed. So with the deck height at 9.010" and the pistons I'm using, how thick of head gasket should I use to get the right "quench"? I also want to make sure I can run on 89 or 91 octane fuel.

 

 

sorry.......GOING to run almost 800ci....798 to be exact!!!

 

hey what is your deck clearance? mine is really close to zero on the setup i have but if yours is above the deck you gotta get bigger than .040, if its in the deck then you "can" run smaller. dont go below .040 quench though. try to get around .045, you just need to add your deck clearance and gasket thickness to get your quench. so run as close to .045 as possible. hope it helps!!!

 

I replied to you a few days ago, I don't know why it didn't post???

My block was decked at 9.010". I don't have any other parts other then my block right now so I can't measure anything. I'll have to wait until I get my crank, rods and pistons. My machinist told me to use a Fel-Pro .039" think head gasket. If I use them and my pistons are .010" in the hole, then my quench will be .049". Is that to much? Other guys have told me a quench between .040" to .050" is good.