The 337 would would Stage VI heads on a low deck block but you would have to fabricate some spacers for the ends of the valley area.
The 337 is the intake to use if you're running original type Max Wedge heads on an RB block. It works perfect in that application by sealing off the valley area. It can also be used with Indy heads and Victor heads but you end up with end gaps that need to be sealed somehow.
