Single 1974 Stage 1 cylinder head

This head is located in Clover, SC. The casting number is 1241860 and it date-coded 10/28/74. I suspect this is a fairly rare piece. It was on a ‘74 455 I recently purchased that had mis-matched heads on it. I doubt I could ever find another one so I decided to offer it up for sale incase someone out there is hunting one. No springs or retainers. Ex valves are in good shape, intakes are pitted on the back side, some worse than others. Asking $250, buyer pays shipping.

 

10/28/74 would be for a 1975 model year car, just saying. I do NOT know the casting number correlation, but as you said (and the casting shows a '4', it SHOULD be a 1975 model year head...

 

Im sure you are correct, I did not have the whole car, just the engine. The casting dates on this head jived with the block, but the other head that was on it was a different casting with smaller valves from 1971. Someone put a single head on it at some point for some reason.

 

No big valve engines in 75 though.

 

Well, it is what it is. This is a factory-made head (hasn’t been modified) and all the valves say GM on them. I’m pretty sure I've deciphered the date code correctly. Either way there's pictures...decipher it yourself.

 

This first pic is of the combustion chamber on this particular head. The area circled in red is shaped uniquely on these big valve castings - it IS cast, it has not been modified with a burr bit.



This next pic is of the combustion chamber on another head that I have with the very same casting number that has the standard size valves in it. Note the difference.

 

John isn't saying it isn't a factory big valve head,..he has owned more stage 1s than most of us here, he is just saying there were no vehicles equipped with big valve heads in 75

It was either a late 74 head or a replacement casting

 

The car that this engine was in was a 1974 LeSabre 2-door that was a one-owner car. The guy special-ordered it and used it for towing. It was a very unique car. Car only had 58k on it when I removed the engine and it did have factory dual exhaust on it...which means it musta had the Stage 1 option. He also said it had a special gear in the rearend, but I never checked it. The car had been sitting for a long time and had been in a flood. It was junk, it was a shame.

 

I’ll get a pic of the date code on the block later today. It is possible both heads were replaced on this engine and they just happened to not match.

 

Here’s the numbers on my block. Does the 5 mean it’s a 75?

 

I have a pair of heads that I took off a 1974 engine several years back that has the same part # as yours and they had the big valves in them.
I thought that it was odd that they were the big valves in the heads - that's why I kept them.

 

Performance Option head, Stage 1 valve size without the swirl polish,..available on the big cars

 

Thanks Larry for pointing out the open/closed chamber thing. That for sure says it can't be a 75. If you had the vin of the car we could confirm if the car came with big valves or not. Big valves were an option in 74. Dual exhaust does not guarantee stage 1 heads.

My guess is the guy overheated and cracked a head at some point. Whoever replaced it didnt realize the car had big valves and used a standard Buick 455 head.

 

It appeared that both heads had been off at the same time. They were both painted a different color and were the same level of cleanliness, much cleaner than the rest of the engine. Who knows what went on here. Either way I doubt I’ll ever find a match so this one is for sale.

 

The date code on this head does jive with the block though, only 7 days apart.

 

“Numbers matching” LMFAO!