Engine code question- 327 vs 350

ChuckN

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327
Just a quick question- truck I bought had a rebuilt engine, but what it is I now not know. Engine casting on by the bellhousing says 3970010 (fairly nondescript- looks like it was used for everything from the '69 302 to mid seventies 350) and the stamping on the front is VO519TYZ. I think the proof is in the pudding, just trying to confirm. Don't care much, has camel hump heads with no accessory holes so I know it's 64cc chambers at most and will have good compression. Just trying to reach out- there's lots of websites out there but some of them are conflicting.
 

AyWoSch Motors

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Just a quick question- truck I bought had a rebuilt engine, but what it is I now not know. Engine casting on by the bellhousing says 3970010 (fairly nondescript- looks like it was used for everything from the '69 302 to mid seventies 350) and the stamping on the front is VO519TYZ. I think the proof is in the pudding, just trying to confirm. Don't care much, has camel hump heads with no accessory holes so I know it's 64cc chambers at most and will have good compression. Just trying to reach out- there's lots of websites out there but some of them are conflicting.
That suffix code fits for a 350 L-LS9 4 bolt main. 165hp, for a 1975 Chevy truck, half ton or 3/4.
Engine was made in Flint Michigan, May 19th, 1975.
3970010, fits with a 4 bolt 350, as it does many other engines. But that's what it is.

For future reference, NastyZ28 is a great sight. Seem to know what there talking about. Has all those codes listed.

If you want a more precise guess on what it was from, I'll need the partial vin that should've been right next to that suffix code, also on the front of the block, on the passenger side head deck.
 

bucket

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They only way to know for sure is to measure the stroke. With older heads on it, it's also possible a 327 crank is in use.
 

ChuckN

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327
Ok, thanks. I was looking at NastyZ28 but I wanted to be sure. The reason I asked is because the guy who sold it, just transplanted, into my '81 C10 told me it was a rebuilt 327 350hp. I'll have to contact him- I know he had an engine shop build it for him, he didn't do it himself and as bucket mentioned, could have just been built as a 327 with a 327 crank. Either way, 350 or 327, is fine with me- it's clearly fresh,
 

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