pwtjr
Well-Known Member
Contemplating two cams for 440:
I am wanting this to run on 93 octane, but am realizing I may be on the ragged edge if I am not careful with cam choice.
With the closing point of the intake valve being the X factor, I am having a hard time deciding between these two similar camshafts. Comp gives their specific valve events on advertised duration @ .015 and Lunati gives their valve events on their card at .050.
Lunati has there's at 47.5 ABDC and the comp goes by the longer .015 # and says their intake valve closes at 66.
My questions for you professionals are:
- Lunati Voodoo Solid Roller #60332 with 273/279 advertised duration, 243/249 @ .050
- Comp Extreme Energy Solid Roller XR280R with 280/286 advertised duration, 242/248 @ .050
I am wanting this to run on 93 octane, but am realizing I may be on the ragged edge if I am not careful with cam choice.
With the closing point of the intake valve being the X factor, I am having a hard time deciding between these two similar camshafts. Comp gives their specific valve events on advertised duration @ .015 and Lunati gives their valve events on their card at .050.
Lunati has there's at 47.5 ABDC and the comp goes by the longer .015 # and says their intake valve closes at 66.
My questions for you professionals are:
- What number do you put in the online calculators? I would assume the advertised full duration, right? I would have to call Lunati to get that exact closing number, or just add 15, which is half the difference.
- So since there is hardly a difference in the .050 numbers, but Comp has a longer advertised, the action on the Comp cam is a bit slower on take off and landing than the Lunati?
- If so, then the Comp cam would in fact bleed off a little more cylinder pressure, thus helping my dynamic compression a smidge more and give me the best chance to run 93 octane pump gas?
- What is a good Dynamic figure to shoot for in my situation? I am hoping the modern heart shape chamber of the aluminum Trick Flow heads will allow me to run on the high side of the recommendation.