need advise on a bare block (350)

[That_guy]

So I am wanting to do a mild 350 build for my 87SS. I found a Guy that says he has a 350 bare block for sale near me. Guy is selling it for 100. I asked him for the casting numbers off it and he sent meV1028TPB. He said it was the stock motor in his 89 pickup, but when I looked up that casting code TPB is a 1971 van, 307, 2bbl Carb... I told him this and he said yea, he saw that too, but it was because it was ancrewcab... He also stated that he had a bad head gasket and one of the heads cracked...

I am planning on getting it bored .030 over to clean out the corrosion he says is in cylinder 7 due to the gasket issues, but am wondering if this is even worth it? I don't want another 305, if I wanted to do that I would just rebuild my current one.

If the 305 and 350 blocks are the same, what is the difference between them. I'm sure I can't build a 305 block into a 350... but why?

 

[SScamino]

The bore of a a 305 is like 3.76? and a 350s is 4.00 I can't remember and the stroke is 3.48.. the stroke is the only thing that is shared between the motors. But even though the stroke is the same the cranks are diff. You can't bore a 305 that far just because of the obvious reasons. If the 350 block is in good shape than just have it bored and honed steam cleaned and burned and have the shop assemble the short block. Than you can build the long block from that.

 

[SScamino]

and hundred bucks isn't bad if it's a short block you can get the crank re finished as well as the rods and have new piston's fitted on.. I've given away 350s before I would have given you one of mine haha, the thing is old guys think this stuff is worth 300-400 bucks and still think the double hump heads are worth 600+ dollars so 100 isn't bad. Go LSX and don't look back haha.

 

[That_guy]

I was questioning it because the casting numbers decode to a 307... not a 350. I guess I could simply measure the bores though. I just don't want to buy a 305 because some schmuck says its a 350.

 

[crotchss]

If the casting number is right and is a '71 chevy 307, you don't want that either. The 307 Chevy had the bore of a 283 and the stroke of a 327, and were junk in my opinion. Just measure the bore, if it's 4.00 you're good.

 

[RITTER]

Why is it even a question, if the casting number says its a 307 then that's probably what it is :idea:

 

[pontiacgp]

look on the ledge at the back of the engine on the driver's side, on an 89 engine it'll have embossed in the cast either 5.0 or 5.7

 

[That_guy]

Ritter, its a question because the seller swears its the stock motor from his 89 full-size crewcab and is a 350. I don't want to get taken in a sale... So I'm asking wiser people than me. I'm gonna measure the bores, but sadly am expecting them to be 3.75 rather than 4.00...

 

[cdg1984]

Make sure its the correct casting number. If you got all that info from that number, I dont think its from the block. If im remembering right, the block casting number shouldnt give you the kind of vehicle it was in or what kind of carb or anything like that. It will simply say what kind of block it is. They used the same blocks with the same casting numbers in all kinds of vehicles. Is the engine pulled from the vehicle? If so, you should just check it out yourself. The number should be on the driver side, behind the head, near where the bell housing bolts up....i think, lol.

 

[RITTER]

Now that I think about it ... there are no letters in a block casting number :|