Heads

Small Block Mopar 273 Cylinder Head
Casting #2658920

Came from the factory with the Combustion Chamber at a range of 61 to 64 CC's.
For every .0065" milled off the Cylinder Head, 1 CC from the Chamber Volume will be
deducted...

The factory virgin combustion chambers typically measure 63.5-64.8 cc. The correct milling numbers for the 920 head is: For every .0053 from the head surface to reduce the chamber volume 1cc. This formula, from the Chrysler Racing Manual, is dead on.