452 heads cc's

In our flow bench testing the 906 flowed better than the
452 or 346 (That were about equal) by a significant margin.
The "F" castings were the best and the "C" castings were
the next best of all the 906 castings.
The 516 old heads were the worst of all.

I accumulated several hundred cylinder heads for testing for our
Stock Eliminator engines.