I have aquired a pair of heads and they have 2 different heads years. Can they be a "set"?
one says 1973 and the other says 1974 I have also noticed one head has a 9 stamped on it and the other has a 10 in the same spot.
Just wondering thats all. Thanks for the thoughts

I was wondering the same, the BBC I just bought has one head made in 79 the other in 82.

Well I hope someone here knows, Im very interested now

I should add that my block is a different year too, so I'm sure the block and heads didn't come from the same vehicle, but did the two heads come from separate vehicles too? I'm thinking this whole thing was pieced together from parts of a machine shops shelf somewhere.

A little story behind this motor. I recently bought it from a guy who said the guy "he" bought it from said it was a crate motor. Which he ended up finding out it wasn't.

Well, a golf club set can have an 'a' brand driver, 'b' brand woods, 'c' brand irons and a 'd' brand putter and its still a set of golf clubs.

Ou have a matching pair of BBC heads (-781). They're just not real close in dates, but that doesn't matter....unless its a year specific motor - blah blah blah....

Well Im kinda concerned a little. I was told they came off the same motor and they are matching. The dates are a year apart that really isnt an issue for me. What Im concerned is the deck surface. Im worried if they are milled that they might be milled two different amounts. Can a machine shop determine this? Thats what Im really worried about

Check the casting number,and see if they're the same.

oh yea same casting # just different year dates one is 1973 and the other is '74

They should,,,we would lay the heads on a flat milling deck and check heights using an indicator. I'd use one that would read out in the .0001's with a total travel of about .005. That would get you down to with 1 0r 2 ten thousanths of an inch.

Just measure the chamber volume. get them close to the same. They are not exact from the factory anyway...