I've got a set of used pistons here, but I don't know who made them. They're flat-topped with 4 valve reliefs, compression height looks like they'd be for a 5.7" rod 383. The only markings on them are "600P" cast into them, but I can't find it in any of my catalogs.

I suspect they might be Sterling or TRW or one of the other Federal Mogul family members, probably cheap rebuilder pistons or something.

Anyone have any ideas?

 

http://www.flatlanderracing.com//str...v-350383c.html

Check part #6.

I thought the 600p was familar, it says H 600P, H for Hyper, but I think you're correct on the TRW

 

Yeah no H on mine, if that makes a difference. Probably hypereutectic, but I'm wondering what the recommended ring gaps would be on these things if I decided to use them for something.

 

If they are Speed Pro/TRW pistons they claim you can use standard ring gaps with their hypers (around .020). I wouldn't run them quite that tight myself, but that's their recommendation.