Camshafts: What effect does increased lift have on performance?

[Kern Dog]

Lets say you have two camshafts with identical specs except the lift.
Same duration, same intake centerline, same lobe separation but one has say .480 lift and the other has .520. What does the additional lift do for performance?
A quickie Google search has evolved (or DEvolved) into experimental AI which could be good or bad, but it stated that higher lift makes more power but primarily at high rpm. It stated that torque was often negatively affected while high rpm was increased.
That seems incorrect to me as that sounds more like the effect that duration has, not lift.
The old fashioned Mopar Performance camshafts always seemed long on duration and short on lift, I assumed it was because they figured that their stuff was intended to be used in Mopar engines utilizing the stock rocker arms and that once you get much past .500 lift, the rocker arms are at the limits in terms of contact patterns on the valve stems.
Hughes Engines looked at it the opposite way. Their cams are often long on lift compared to the duration numbers.
What are your thoughts?

[armor64]

I feel that high lift works if you have enough flow to feed it? high lift lets more air move into the vacuum of the cylinder, as the valve "gets out of the way" more, but if the intake and carb are a bottleneck, i think the lift wouldn't matter for some stock or low-flow parts? and at high RPM, the gap is larger to let more air go past the seal faster, likening it to "the door closes so much faster, so to fill a room, it needs a wider entrance to get people through".

[b5blue]

  Hopefully by March/April I'll have real world results to compare for what you propose. I've been freshening up my 69 440 and installed a new Hughes cam to replace my old MP "resto" cam.
  The stock 74 vintage 440 has quite a bit of power running my Sidewinder aluminum heads. (With the CH4B and a Proform 750 on top.)

[metallicareload99]

I've always looked at cams by duration first, and the more lift for the given duration, the better. The valve dwelling longer @ higher lifts should make more power

[Nacho-RT74]

I guess because the air not just flows throught the valve hole but also the virtual cylinder created between the valve seat at head and the valve itself. More lift also a higher cylinder, so more area without obstacles to flow... less resistance to the flow.

And if we consider the valve stem thickness... we'll, more to win/loose.

[b5blue]

I was just going to replace my MP resto cam with a new one but they are no longer being made.

[Kern Dog]

Whoever was making the cams for Mopar Performance seems to have quit doing it but that was awhile back. I recall seeing the leftover stock priced way higher than what was expected, almost to the point where you could get a roller cam for the same money. You'd have to be a thick wallet enthusiast wired real hard for nostalgia to pay $500 for a "Purple Shaft" cam.

[b5blue]

Exactly what I ran into. I called "Mr. Sixpack" and his supply line is so sloppy he sent me to Hughes. Even they warned me that all supply lines can run in fits and starts. Not one to monkey around I ordered my SEH2024BL-11 that same day.

[cdr]

It all depends on the head flow, at what lift point the port maxes out on flow, lots of heads flow worse at a higher lift point.

[Q5XX29]

Swap from factory 1.5 ratio rockers to some 1.6 ratio and find out! For most mild to moderately modified 383/440's, you'll pick up 10-20 hp (perhaps a bit more if you're also upgrading from conventional to roller rockers)