Black & Red Posted November 12, 2014 Report Share Posted November 12, 2014 I'm noticing a trend in 4.6 2V camshafts to run less lift and duration on the exhaust. We sometimes did this on NASCAR or other endurance applications, when cylinder head exhaust flow was more efficient than intake flow. At what point doe the 4.6 prefer less lift/duration on the exhaust??? I would think that a street motor with stock exhaust manifolds would prefer more lift and duration on the exhaust and a 4.6 with long tubes would likely prefer less lift and duration on the exhaust. Thoughts???? Link to comment Share on other sites More sharing options...