Just got a 3970010 4 bolt. I found as many numbers as I could on it.

Head numbers is what I have the question/concern with.

Pass side is 333882 GM37 F237

Drivers side is 3932441 GM20 A81

Appartently they do not match. All I do know is that they are both 76cc.

Can anyone give me any more info on them? Thanks.

From www.mortec.com (http://www.mortec.com)

333882 74-80 350/400.... 76cc
3932441 69/70 350........76cc

The 441 probably came on the engine, and the other one was probably replaced later on. The 882's were some of the first emmision SB heads, and are thinner than the older 441's. I think they have an additional exhaust crossover passage too. If you're goint to match them, go with the 441. BTW, does the 441 have the small seat plugs, or the large gasket seat plugs?

If you mean the spark plug threads, they were small diameter. Also I do not intend to go nuts on the motor, so finding another 441 I assume would be the way to go? I currently have a 68 malibu w/ a 307 and intend to just put a good rebuild kit (any suggestions) on the 350 with a mild cam and edelbrock 2101 manifold and a nice carb. Thanks. Rich


Also, what about 333881s or 330545s are these worth searching the local yards for?

I tried to reply to your email, but AOL SUCKS BIGTIME :mad: anyhow, here's what I wrote

Some of the 441 heads had large seat plugs, that's why I asked. Keep that in mind when looking for another one. The heads are interchangeable from left to right. Here's a cut and paste from mortec.com on the heads you have

3884520....60-67...283..........Some marked "Made in Canada", 60cc chamber, also used by Studebaker
3884520....62-67...327..........Some marked "Made in Canada", 60cc chamber, also used by Studebaker

I'm assuming these are on a short waterpump setup. They would bump your compression up quite a bit if you used them on the 350, but the vortec heads have roughly the same size chamber, but flow a lot better.
Another cut and paste from Mortec

3914678....302.....68....2...Z-28 Camaro
3914678....327.....68....2
3914678....350.....68....2

If it is an 8 on the block casting (I couldn't find anything close with a 6) you have a 327 going by the above info stating the 520 heads were on the 327. It has the same bore as the 350. Might be worth working ;) 327's can be nice screamers.

So what should I look for at the yards to replace these with? (The 350 heads)