Technical Head stamp ID help

Hello all, I'm in the process of tearing down and redoing a 1940 chevy, it has a 283 small block that sounds like a mild cam in it and runs good. Anyway trying to figure out what the heads are. The stamp looks like 354484 but I think it might be 354434? I assumed double hump by the two castings. I can't find anything that would be a camel hump with that number. Thanks for any info.

 

Josh....for the purposes of terminology...those are casting numbers. 354434 is a 262/267/305 head...Chevy had some weird small V8s in the mid to later 70s. The casting date J26 76..is October 26, 1976 for a 1977 car. Sorry no camel humps here..

 

Thanks for the reply, I was kinda figuring as much. Did GM put the old "hump" casting mark on the heads just for nostalgia or trying to fake people into thinking they had something they don't?

 

The top image is the original “double hump” casting identifier and even though some do not consider the bottom one a double hump it is, but was modified because Chevrolet changed the heads to include accessory bolt holes.

 

yours is not two humps...it's a rectangle, with a round notch in it.

 

Ok, ya now I see that. It just looks similar i guess to humps. Thanks guys for the replies.

 

The symbols cast into the end of the head is for the foundry worker and assembly line guy to identify them. They don't have time to read casting numbers. All the heads have different symbols cast into them so they can be identified on a rack..quickly. We have come to associate certain symbols as high performance or desirable heads...while that is a lucky tool for us...it wasnt GM's original intent behind them.

 

Such a wealth of information on this board guys, I learn something every day. Thanks.

 

Double humper camel toes on my mystery 283

block casting 3789935 - ‘61-64 283
Block ID stamping F022IN - ????
Date code B182 - Feb 18 ‘62

 

75/79 small valve heads as the others said. Good for a street driven 283 that isn't a high performance engine as they have hardened seats and rotators on the valves. Not a lot different than a pair of power packs performance wise but they aren't going to impress any mouth breathers like a pair of camel humps might. Meaning that if you are building a mild engine that you want to get a lot of miles out of with little hassle they are a pretty reasonable choice. Probably why they were on the engine in the first place.

 

Thanks for the info. Somebody put a fake supercharger housing over a period correct 2 barrel carb, Rochester, made a janky plate to a Edelbrock 4 barrel intake. Still scratching my head on that deal. Anyway I've got a new 600 cfm Edelbrock on it and it is really snappy now, just working on details and un ratty a few things.