The Ford Barn

Bruce Lancaster · 03-09-2015, 11:59 AM

One thing is cold piston shape...the small-block Chevy at some point in its history went through a lot of development of piston shape so the irregular lump would assume a round shape as it heated. I think Yunick was involved in this. That's ancient history now, so I would imagine a lot more work has gone into that endeavor. Also, top rings have moved upward, presumably influencing the amount of heat reaching lowe part of piston.

I don't own any actual manuals for anything remotely modern...a quick look at the google kicked up this chart of Toyota clearances up to 2005. Will give URL as columns don't behave when copied... http://www.autozone.com/repairguides...96b43f80380186

03-09-2015, 11:59 AM	#1
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: Tight Piston Clearance, Not Model A One thing is cold piston shape...the small-block Chevy at some point in its history went through a lot of development of piston shape so the irregular lump would assume a round shape as it heated. I think Yunick was involved in this. That's ancient history now, so I would imagine a lot more work has gone into that endeavor. Also, top rings have moved upward, presumably influencing the amount of heat reaching lowe part of piston. I don't own any actual manuals for anything remotely modern...a quick look at the google kicked up this chart of Toyota clearances up to 2005. Will give URL as columns don't behave when copied... http://www.autozone.com/repairguides...96b43f80380186 Last edited by Bruce Lancaster; 03-09-2015 at 12:06 PM.