Piston identification question..

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Haffy

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First post ever, woohoo! Quick question, can anyone ID these pistons? I have a bit to talk about, and questions to ask but that will be a later post.. Trying to get organized to do a junk yard 350 build for my 84 C10..

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Charlie

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Honky Kong jr

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Which engine are they in a 305 or 350. They are dished pretty deep I’m guessing 305 to counter act the smaller combustion chambers of the 305 head. Most 350 pistons you see have 4 valve reliefs. Just my .02
 

PrairieDrifter

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Also looks like it’s a standard size. Hasn’t been rebuilt or rebored for that matter. Can’t see any markings on it that would indicate otherwise
 

HotRodPC

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Looks like some stocker style Wee O Five pistons IIRC. Maybe even 267 pistons since I was thinking Wee O Five pistons had 4 valve releifs. :shrug: I know it's not 350 OEM pistons and as said, doesn't appear to be an aftermarket piston with any oversize markings on it anywhere. I'd just be guessing at best, but they're NOT 350 OEM's for certain.
 

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I thought stock 305 pistons were about 10cc dish with no valve reliefs? Guess it depends on the year break/smog requirements of the era. Probably learn more about it by running the numbers off the block.
 

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Thanks for everyone's help! I'm going to knock the block apart this weekend and see what I can find. All I do know is that this is a 350 4 bolt, and it has been apart at some point. The pic sucks, but it has clean crosshatch and it had 882 cyl heads on it. The crank has some pretty heavy scoring on one of the mains, so I'm debating if it's worth putting a crank into (I have a lead on a used Eagle for a great price).. I will keep posting as I go!!
 

HotRodPC

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I thought stock 305 pistons were about 10cc dish with no valve reliefs? Guess it depends on the year break/smog requirements of the era. Probably learn more about it by running the numbers off the block.
I've seen those too. So it is aftermarket pistons, since he mentions it's a 350.
 

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I've pulled apart stock 350's with dished pistons? I don't remember which engines they were, but I know I've seen them stock.
 

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I've pulled apart stock 350's with dished pistons? I don't remember which engines they were, but I know I've seen them stock.
Yes, many 350's have dish pistons. Usually 4 valve reliefs too.
 

Haffy

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So, I pulled one out because curiosity was killing me.. They have B 563 cast inside them, and they measure .060 over.. I found 1 mention of that # in the Google, it was in a 1985 4.3 that had been rebuilt. So, unless I can ID the quality (& strength) of them and the rods I'll keep hunting for something else.. Either a rotating assembly or a complete shortblock..

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HotRodPC

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That sure likes like a thicker than normal skirt on those. Or maybe it's just the pic, but that looks like a thick piston skirt to me. See if any agrees or not. The rods appear to be stock OEM H beam rods IMO.
 

PrairieDrifter

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The rod definitely looks stock. As for the piston I’m not completely sure, it honestly looks like the side on the bottom is way thinner than the top side. It doesn’t look stock though
 

Haffy

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The skirt is .160, the compression ring is .075, and the intermediates .080..

Anyone have any thoughts? I have a 292H cam, and some decent heads that will give some good compression..
 

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