I'm trying to find out as much about my car as I can. Thats the part # off the heads under the valve cover, so I'm trying to figure out if its a self port job, or the guy sent in the heads to get ported and got a different year back.

 

Thats a common # for LT1.....

350 ALUMINUM HEADS - There were two versions of the aluminum heads used on the Corvettes, Camaros and Firebirds. The later ones have less material around the top of the intake ports and weigh about 2- 1/2 lbs. less than the earlier ones, but they are identical otherwise. Look for a 10128374 and possibly a 649.

 

I thought the 649's were for the 97's and the 10128374 are the previous years?

 

This is all I found... Scroll down... with 3 casting # s'

92-up 10128374
93 10205245
94-96 10207643

http://www.mortec.com/castnum.htm

 

The #374 was introduced in '92. The 374s were used in '93? I am also aware, GM introduced another casting # in '93 (see above). So, your guess is almost as good as mine. I am aware of a total of 4 castings #s through '97. Let's not forget the notorious #561 castings. So basically.......I agree with above post.

 

So I don't have 97 heads?

 

I agree with Arnie, and a great deal of the heads we've had that supposedly came off of 97's were 561's. Probably 90% of the castings we see are the 643's. I still havent come across a ruined '374' head yet, but if I ever do I'll section it to see if there's any truth to the rumors.

Those may have been original, as I've seen 374's on 94's and supposedly a 95 or two.

For most guys, I wouldnt even worry about what casting you have, because even the worst casting is capable of safely flowing more than most shops are likely to get out of them.

Hope that helps a bit

-Phil

 

Well, ok, but remember, the guy has a '97. With "supposedly a 95 or two", (as post production 'stragglers'), this doesn't give the guy good odds, to stretch it out BEYOND another production year. I'd be more inclined to state it is highly unlikely the #374s on his '97 are original. Dislike building the guy's hopes up.

I got news for you, fella. I agree with you more than I let on. I'd don't like the idea, of info of this nature geting out, so I should delete this post shortly. Would kinda ruin some of the drama on this forum.

 

LOL, no I agree with you, it's highly unlikely, but I've learned to just present what I've seen & let people draw their own conclusions. Lest they revolt against you for telling them the truth, as it's rarely what people want to hear

What is the world coming to?