New 340 should I use X or Edelbrocks???

sounds like u have two sets of heads that flow about the same, but one will have mote energy 'heat in the chamber'-iron. Both r open chamber....and one is lighter weight....so which will give more benefit, hmm..lol
Run the X's and have the eddys ported, take advantage of them befote wasting time and gaskets to end up neck and neck.
Btw, most people dont know how to get bigger numbers out of old iron...so its no wonder why a set of ported eddys picked up over a set of ported x's.
the old heads will go 280's cfm 'full ported' while eddys will go 290's-300cfm.
Though if u have someone above average like iq52 porting them, well...now the ceiling just got higher.
I have 3 sets of old iron that go 260's-280's cfm fwiw.
cuda, so were the the low lift numbers butchered? or was the cam just wrong for the flow curve?, i have trouble understanding how the car could slow down.