lycoming O-320

a lycoming o-320-e2a is for sale and is supposed to have the 8.5 to 1 compression ratio pistons.

but the engine records are not clear on which pistons were used at last overhaul.

my question is: how do you confirm which pistons are in this engine? (without disassemble of the engine)

thank you for any and all replys.

Compression

The CAFE Foundation in Santa Rosa CA devised a method of measuring piston position at top dead center and then comparing it to the same measurement on a known engine.

Attempt to contact the shop that performed the last overhaul and give them the serial number in question. They should be able to produce the parts list list used.

Minimum oil temp?

---oops, posted in wrong place!__