5.2 Magnum Piston Question

Max1196 said

No #'s stamped on the crown? They look like a UEM 1266c or a Sealed Power 285np (these are for a earlier 318), which have valve notches. Not a UEM 3234H or Sealed Power H526AP or H814P,for a Magnum, which have no piston notches. Differences also are ; ring thickness, weight, compression distance, cost and no full float pin for the Magnum choice.
They sure look like these, S/P 285ncp's stuffed in a 350 Pontiac.
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Ah okay thanks!

I haven’t picked up the rebuilt short block. I will take a closer look at it and look for numbers.

I am guessing they might have used older LA 318 pistons in the magnum then.

I’m on the fence now after looking up those part numbers, this could be lower compression than the motor I’m currently taking apart.

I take it the piston rings might not be as good as the magnum ones as well. Here’s a picture of the Magnum I have.

It could also be that it’s not a magnum engine then huh.

I’ll take some pictures when I go take a looks mad I’ll add some of what Incurrently have.

Sounds like my Stock magnum might be a better choice for the swap?