Olds Piston Info??????
 

Does anyone out there have any idea what this piston # identifys. It should be a TRW or Speed Pro item if i'm at least on track. Its a forged .030 over # L2278P. --- Thankyou.

Re: Olds Piston Info??????
 

I think (going by memory) that is the old deep dish 455 piston. Should be around 4.120" diameter, plus whatever over size is marked, have a deep dish (maybe 0.250" deep, and almost the full diameter of the top of the piston), 5/64" compression ring grooves, a 3/16" oil ring groove, and compression height should be around 1.760" (going off of memory), with a 0.980" pin. Useless for anything but a very low compression engine, around 8:1 or so, unless you deck the block a bunch, and mill the heads as well. It usually comes up about 0.060" in the hole on an undecked block.

Re: Olds Piston Info??????
 

According to an old TRW catalog, a L2278F is a 350 Chev stroker piston with a compression height of 1.52". 3.562 stroke using 5.7 rod. I don't see any "P" suffixes, but this is a 'Performance Components' catalog and doesn't list any pistons that aren't forged. Hope this helps.

Re: Olds Piston Info??????
 

455 68-70 all 4-bbl. 1.710 0.980 5/64, 5/64, 3/16


2278P Sealed Power