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Message: <blockquote data-quote="Notthenow" data-source="post: 1486470" data-attributes="member: 23871">Thank you Blak, I appreciate the time you have taken and thoroughness of both of your replies! I thought there would be a simple mechanical range to measure and so I did not give enough details of why I asked both questions. So, the long winded, detailed explanation, first, I asked about squish because I am in the middle of a pi head install on my 98 which has 160k on it, but did a good compression test before tear down. I am also installing Comp 262AH cams. I ported the heads meticulously going by port to port measurements. I know a flow bench is the best way, but I the heads were $120 and I wanted to learn. I installed bronze guides and re-cut the seats in 3 angles using carbide cutters. I installed new stock exhaust and titanium intake to reduce the margin for help with ptv, as well as Comp springs and new seals. Then I cc'd a chamber on each for reference. Right bank 42, left 44. I'm assuming one head was cut in its lifetime (heads are off a police car in a u pick). This got me thinking about compression ratio and juggling gasket sizes. That led me to your post on quish and checking piston to head clearance. My block varies from bank to bank and within the banks themselves. I am scratching my head to balance compression ratio and squish without a trip to the machine shop. Sooo, after all that....stock piston in the hole should be .012 and stock gasket compressed should be .036.  Total of .048 factory quish.  In your other reply you mention a few thousands under should be safe, so roughly .045 as a target.  My block measures .006 for the shallowest piston (maybe decked before, although stock pistons). I am looking at Mahle head gaskets because they offer a plus .010 (it is actually .043 compressed per their tech line) that is cheap compared to Cometic. The problem is then in balancing the compression ratios per bank dues to the 2cc difference. The calculators show up to .2 difference between banks and I wonder if that matters in a mostly stock engine (about 10.4 to 10.6). Maybe that is common and no one realizes since most don't measure?And that is the origination of my two part question of safe squish and compression ratio variance between cylinders.Sorry for the book, but I hope the background helps as I am trying to be careful without be paralyzed by numbers. There are numbers out there for Chevy, but with the small bore of the Ford mod I wanted to not assume.</blockquote>