Info on 340 HP

I'm new to this engine, and have a question on how to identify a 220 hp 340 from a 260 hp 340.
can anyone help. I bought a 340 to go into my 67 Buick Special. Thanks,

 

The difference is the 220 HP has 2 bbl, 9:1 compression and the Engine Code is MA
The 260 HP has 4 bbl, 10.25:1 compression and the code is MB.

The Code is stamped on the right side of the deck between the center of the exhaust manifold.

 

Is the only difference the 4bbl carb?

 

Also the higher 10.25 compression as Micheal posted.
Don't know if the cam had slightly different specs?

 

Pretty much, the Buick train drivers designed a one cam fits all type of deal, I would guess the sbb 300 has the exact cam as the 340 engines as well.

I would imagine the bean counters of back then had something to do with that too.

And welcome from SE Michigan!

 

Thanks all for the info, from the north east