Except those that came with 250 heads, which are almost exactly like 906s. Or was that only on '68s? The deal was that Chrysler most likely didn't have the volume to support a low-perf AND a high-perf head like chevy did. That's one of the fun things about Mopars. Most any engine can be made to run strong without changing major components; blocks, heads, cranks and rods.

Anyway the 906 head features prominently in MOPAR mythology, even though any B/RB head made from 1968 on has the same lousy combustion chamber and virtually the same flow characteristics. Check out the Tech Archives.

R.