Originally Posted by Midvalley

crane cams use the flow levels in the upper lift ranges where bigger heads seem to flow better (shorter duration higher lift) and a comp cam works better where the heads need dwell (longer duration lower lift) the reason jet boats work well is they are generally water injected exhaust and water flow is minimal until the upper rpm ranges and they also jump right to full RPM from a stand still and increase pump load as the boat accellerates, a prop loads just the opposite so that lower RPM loading causes a totally different exhaust resonance where overlap creates problems...

Originally Posted by Midvalley

crane cams use the flow levels in the upper lift ranges where bigger heads seem to flow better (shorter duration higher lift) and a comp cam works better where the heads need dwell (longer duration lower lift)

Originally Posted by f_inscreenname

Don't know it will help...
I've used a few different cams in my Mark IV roller / stroker motor. but have been pretty happy with ⦁ Howards Cams 120255-12 - Max Torque Retrofit Hydraulic Roller Camshafts, Hydraulic Roller Tappet, Advertised Duration 288/294, Lift .585/.610, 112 L/S

Originally Posted by getrdunn

howards does have some good grinds. Not sure what their cores are like but I refer to their cams often when looking.

Originally Posted by endeavor1

Looking thru the Comp love catalag, the 3370 cam profile looks like a step up from the crane 651. What I gather is similar duration, more lift. Fun killing time looking thru the various cam company’s master lobe list.