Jesse,

I would get with Bret or Phil and tell them what kinda Maximum RPM you are wanting to turn and what Minumum RPM you need power at.

I am pretty sure that thise are single springs that can handle .600 lift but for a cam that size, a double spring would be MUCH better. Even though the springs can handle .600 lift and still have some coil bind clearance, the XE lobes are FAST and will float the valves (or wear out quickly) on a cam any where near that size. The cc306 or XE 230/236 would be as large as I would wanna go with those springs and that if you twist 6500 RPM or more, these cams would still be better off with a dbl spring.

There is alot more to it than just the duration at .050. The valve timing events (IO, IC, EO, EC, overlap, ICL, LSA, etc) are more important than just "going larger" on the duration.

Phil or Bret will be able to get you a cam that will "work' right instead of a cam that is "just larger". I would at least talk to them and listen to each of their theories and opinions before buying a "larger" cam.

NightTrain66