400BB Engine

Tacfire;

BB means Big Block. The 400 is a "B" series big block. Others in the "B" series are the 350, 361 and the 383.

The other Big block engines from MoPar are the RB, for raised block. (Height mentioned earlier) and the RB based HEMI. Theres also lots of other HEMI engines, but they are old.
The MoPar 400 is very close in it's bore and stroke like the Olds 400 found in the "Bandit" Firebirds.
The 452 head has a bennifit of hardened seats for the exhaust valves and can be ported out for very good results.
I currently swapped one into my Magnum (79) from a Cordoba (78) and can agree, it's thirsty and theres no power to it. Then again, the mid '70's performance fel of and continued to fall, rather harshly to the point that even big engines could barely squezze out 250 HP.
This all changes with piston replacement for decent compresion and a cam for better power. It's hard to mill the heads enuff for decent compresion since I measure my pistons down the hole a stagering .112 or so.