Originally Posted by retiredvet
Yes the wide quick open close is what gives you the lope
Sent from my LG-D415 using Mustang Evolution mobile app
Ehh, valve overlap is more of the central topic.
Modern engines all have really steep cam profiles. Steep cam profile is actually why modern engines DONT lope like the old ones. The engines have more static compression because of this. The valves don't overlap as much anymore.
Think about the ghost cam tunes. All those do is add valve overlap with the stock cam's lift and duration, but it still chops pretty good. It would chop even more if the cam profile was more gradual, so there was more valve overlap.
Lift and duration definitely are factors in how choppy it sounds-- because those increase the valve overlap and decrease the static compression even more. the eccentuate the phenomena that makes it lopey