340 TA with x heads ? or not

Correct Krazy Kuda,

No big difference in 'Flow' between the 'X' Head and 'J' Head.

#3418915 'J' Cylinder Head

The stock 'J' heads will flow at

Intake..... 205 CFM @ .400" Lift and 220 CFM @ .500" Lift
Exhaust... 145 CFM @ .400" Lift and 148 CFM @ .500" Lift