piston to head clearance - Page 2

Greg Reimer 7376 · 01-24-2009, 02:43 PM

Some time back,I put together a 327 with new pistons(TRW cast replacements) as a backup motor,used the FelPro .017" gasket, and set the deck at .013".Six pistons had.030" deck,one had .028",one had .026". It ran fine(although not a real fast engine, it was a rather reliable mule motor. I had to replace head gaskets and freshen things up after a while, and noticed that the .026" piston had a very faint imprint of carbon in the shape of the cylinder head deck surface. After wiping it off,no trace of a mark on that piston. Somebody who tells me they have .020" or less total deck on their 327 or 350 and turns the engine 6800 or more is asking for a REAL problem,although you probably wouldn't hear it. It's best to use the thinnest head gasket available and give up more down in the block on top of the piston in order to keep the CR as high as possible.With that piston and rod combo, the .026" deck would be the ABSOLUTE minimum to shoot for.

01-24-2009, 02:43 PM	#11
Greg Reimer 7376 VIP Member Join Date: Nov 2008 Location: Glendora,Calif. Posts: 1,116 Likes: 166 Liked 655 Times in 209 Posts	Re: piston to head clearance Some time back,I put together a 327 with new pistons(TRW cast replacements) as a backup motor,used the FelPro .017" gasket, and set the deck at .013".Six pistons had.030" deck,one had .028",one had .026". It ran fine(although not a real fast engine, it was a rather reliable mule motor. I had to replace head gaskets and freshen things up after a while, and noticed that the .026" piston had a very faint imprint of carbon in the shape of the cylinder head deck surface. After wiping it off,no trace of a mark on that piston. Somebody who tells me they have .020" or less total deck on their 327 or 350 and turns the engine 6800 or more is asking for a REAL problem,although you probably wouldn't hear it. It's best to use the thinnest head gasket available and give up more down in the block on top of the piston in order to keep the CR as high as possible.With that piston and rod combo, the .026" deck would be the ABSOLUTE minimum to shoot for.