I was just picken at those preaching about lift
no hard feelings here!

 

Something I happened on in another thread here is that this cam is in fact a custom Comp grind on XR lobes, and sure enough its in a Comp box with a Comp cam card
Weather is starting to straighten out here...I can't wait to get this puppy in.

 

So what you all are saying is that with the stock heads anything pretty much above .550 lift is useless. What if I were using 799's milled .030 and some port and polish work, nothing extreme just smoothing out the roughness of the 799 casting, then would lift above .550 make a difference and how much would it take away from low end?

 

Every GM LS head I know of flows great up to .600 even stock. Here are some flow #'s.....
http://www.smokemup.com/tech/ls1.php

 

Duration and LSA both figure into ovelap, if you take two cams with the same specs but different LSA's, the one with the tighter LSA will have more overlap, and more overlap = more "lope/chop", among other performance characteristics such as bigger peak numbers

 

I'm interested to see how this thing does...

 

What Rhino said above. As long as the flow doesn't DECREASE in the valve lift curve you're golden. You just have to worry about ramp rates and appropriate spring rates to control the valvetrain mass. There would still be a benefit to going with a cam with .600" lift at the valve in a head that only flows 1 or 2 cfm more compared to at .550". You've got to think about how much more "area under the lift curve" there would be relative to a cam that had a max lift of .550". If you've got a head that stalls out (or reduces cfm) past a certain lift point, you'd want to stay below that for sure, as that would cause severe issues with flow continuity in the middle of the intake stroke. Biggest thing here I still think would be ensuring your valvetrain components are all matched to handle each other (spring rates, lifter capabilities, rocker positioning on valve tip or clearance issues, pushrod strength relative to loading, and PTV clearance).

 

+1 I never understand why I keep seeing people say that on here about cams with over .550 lift and stock heads. Just because they flow about the same from .550 to .600 doesn't mean you're not gaining anything.

A cam with .600 lift is going to spend a certain duration between .550 and .600 which would be max flow for that head. A cam that peaks at .550 will spend 0 time in that range.

And if the lobes have the same profile, then the higher lift cam is going to get to .550 lift sooner.

 

Well lookin at that smokem up link a cam with .581 in a lq4, as in my 01 6.0 would be still be useful.

 

Did we install this cam yet? Looking at it to help promote mid-range torque in my 5.3L.