Small Block Cylinder Heads 'Stock Specs'
Correct TX-Stang-84,
The #3418915 'J-Heads'
'J-Head' Combustion Chambers are typically at 68.0 - 72.0 CC's.
Also, the Intake Port with the 2.02" Valves has measured as much as 3 CC's less than the
'X-Heads' {157 to 160 CC's}.
But, the Exhaust Ports on the 'J-Head" have measured as much as 3 CC's larger than the
'X-Heads" {73 to 70 CC's}.
Port wise, they are nearly identical, with a very minor variation in Port Volume.
I'll post the 'J-Head' specifications later.