327/350HP Head Numbers
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Joined: Oct 2013
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327/350HP Head Numbers
I just bought my first corvette. 1968 that needs some tender loving care. I have began to pull it apart and am planning to do a complete restoration. I have the engine out and am confused on the head casting numbers. The block is #185S401198 V0926HT which I believe is a 327/350HP. The heads are #3917291. Research says that these for the 300HP instead of being #3917292. All other numbers seem correct on everything else. The heads also have a H227 stamped by the casting numbers and a GM17 and GM18 casting number. Can someone tell me if these look correct and what I actually have?
Melting Slicks
Joined: Sep 2007
Posts: 2,149
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From: cary Il
the head casting #s would be the same but the 350hp heads had bigger valves. date = aug 22 1967, block should be 4 bolt with upgraded hardware, rods,crank,pistons, 8" balancer, deep grove pullys. good luck with your project.
Burning Brakes
Joined: Dec 2010
Posts: 848
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From: CA
3917291 heads came with either 1.94 intake / 1.50 exhaust valves (327/300) or 2.02 intake / 1.60 exhaust valves (327/350) so they're probably the original heads for your engine. The only real way to tell is to pull them and measure the valves.
No 327 came in a 4 bolt main configuration, so you should have 2 bolt mains. (4 bolt mains for the small block didn't start until 1969 and then only on the 302 and 350 high hp engines.)
Ed
No 327 came in a 4 bolt main configuration, so you should have 2 bolt mains. (4 bolt mains for the small block didn't start until 1969 and then only on the 302 and 350 high hp engines.)
Ed
Last edited by restoman1; Oct 29, 2013 at 09:46 PM.
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