That's another issue. How damned MANY types there are. Econo, race, long valve, short valve, open, closed chamber. WHY would Mopar ever make a W2 RACE ORIENTED head that accepted standard length valves? Makes ZERO sense. Most anybody lookin at the W2 would want long valves for a better spring anyway. Some things Mopar did in the mainstream AND aftermarket I scratch my head about. I mean, you got a head with ports that can potentially flow to .800 lift and make a version with short valves. LOL