88 350 tbi tear down. Heads and piston question

[rfriese]

I finally got the heads off my engine. First tear down of a V8. Better late than never.

1. Engine painted blue not stock.
2. Pretty sure a rebuild. it has overheat indicators on the heads. Pioneer 580 plugs on the ends of the heads.
3. Pistons are not original. Stamped 345np .040 dual valve reliefs pn#02-233-04b.
Any ideas on the pistons and heads being an upgrade or just a replacement?
Thanks for all the help.

 

[dsteelejr]

There are folks on here that are a lot more savvy about engines than I, but you can always start by entering PNs into a part dealer’s website like Summit, Jegs, Napa, etc. A quick search on Summit didn’t find PN 02-233-04b, but 345NP came up with Sealed Power brand cast pistons. Cast pistons are the cheapest, with hypereutectic and forged being a higher grade piston. They were probably replacements, not upgrades.