I purchased a complete running 4bolt 350.
I yanked the heads and pan off.
I saw flat tops with 4 valve reliefs and a small circle in the middle of them.They also have arrows facing forward.I think they are either stock pistops or cheap rebuilders.
I saw the part number on the skirt.It looked like either 8557 or B557.
Anyone know what it is and what the "Advertised" compression is with 67cc heads?
I brought the thing to top dead center and layed a feeler gauge on the piston and roughly figured the deck height at .055.
I'm probably going to run a Fel-Pro .015 shim gasket.
No, this is just how they are described in the catalogs.
I don't have a clue why I guess it was someones idea of an easy way to tell you the pin was moved without simply saying the pin is moved up .020.
It is a 350 piston with the pin moved up just as they do in "stroker pistons" only some bright spark in advertising or what ever decided to give them a 'cute" name?
Why are we even discussing this, it's a piston with horrible quench with a stupid name designed to be put in a block that may have been decked.
Hey, all is not lost
You can get it to a smokin 8.4 with a .015 1094 felpro & 76cc heads or better, 9.5 with some 64cc vortecs
This is assuming they are really .055 down which is .010 further than they should be unless the rods got "destroked" .010 when they were done too
Don't feel bad. The engine in my truck has 9.4-1 with vortec heads, .040 deck height, and .038 head gaskets. Yeah, thats right...078 deck height But, I built the shortblock back before I knew much about quench. I use an XE268 (which would work great in your application BTW). I get 180psi cranking compression, run on 89 octane (87 in a pinch), and can burn the tires off of it from a 15mph roll with 3.08 gears and a 2000 stall convertor. It's not perfect, but it gets the job done.
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