Lift is the amount the valve opens,higher lift allows more air/fuel mixture at least in theory.To acheive higher lift at a given duration requires faster ramps on the cam lobes.The advantage of the higer lift versions of a cam is more usable duration due to the faster ramps putting the valve at a usable lift point sooner.The dissadvantage is the stess put on the valvetrain due to the faster ramps.The extreme ramps used today are only feaseable due to the use of roller lifters to keep contact with the cam lobe and improved valvespings to keep the valve from floating.

 

Thanks for the link Tib. Very informative.



Thanks for the replys guys. I learned something new.