camshaft help

I am looking to change the camshaft in my 67 4spd valiant, the car has a 451 big block with about 10.2:1 compression, iron heads ported by muscle motors, mopar single plane intake with a 850 speed demon carb. It is now setup to go with a solid roller cam, so that is what I intend to do.(not impressed with the hydraulic roller that is in it now) The cam I am looking to get is a comp cams XR292R specs are duration @ .050 I/E - 254/260 with lift of .582/.588 on a 110 LSA. I would guess with this cam, the iron heads would be holding me back and I will address that later. As a baseline the car ran 116.5 mph(my disappointment) in the quarter on a small hydraulic roller, duration @ .050 I/E - 230/236 lift - .528/.539 on a 112 LSA. My goals for the car with the cam swap on the ported iron heads would be to run 121 mph trap speeds or better. Does this seem like a reasonable goal for the cam swap? Does anyone else have other comparable cam suggestions? Experience with this cam? Aluminum heads will come later, Indy EZ or bulldogs ... not sure yet, then I will expect some serious pump gas power :thumrigh: Any input is greatly appreciated

-Nate