Hard to find info including dyno numbers on the Cam Motion Stage 2 cam designed specifically for the 6.2L truck engines. Anyone have any experience with them or thoughts on which version to roll with? I ordered the low lift version but still have a little time before they start the production of it and could switch to the higher lift version if needed. It's for a 2012 Yukon XL Denali. Pulling out a damaged BTR stage 2 cam (story in another thread) and want to go back in with something that will still be reliable, durable, quiet, and suitable for pulling a 7000 lb camper. They offer it in 2 profiles:

"Drop-In" Version:
Grind # XA212/295-XA220/295-17+5
Duration at .050 - 212/220
Lift with 1.7 - .501/.501
Lobe separation 117
Intake center line 112

"High-Lift" Version:
Grind # XA212/325-XA220/325-17+5
Duration at .050 - 212/220
Lift with 1.7 - .553/.553
Lobe separation 117
Intake center line 112

Questions:
1/ How much power difference would you estimate there'd be between the 2 versions? Up high? Down low?
2/ Would the "high-lift" version likely require more care and feeding (e.g. new springs) in the next 100K miles? Note: I already have upgraded BTR beehive springs capable of handling the higher lift version
3/ Would the valvetrain likely still be as quiet with the higher lift version as the lower lift?

Thanks for any help and input you may have. I'm grateful.

 

Probably 25-30hp difference. Should be pretty similar down low, but with more mid-range and peak power on the top end. The stock rectangular heads flow so much better at .550 than .500 (and even keeps going above .600!). On a stock cathedral port you wouldn't see as dramatic a difference.

Since CamMotion uses about a 55 intensity from .050 to seat-to-seat timing, either should operate quietly with proper length pushrod. And I doubt you'd be taxing the springs on the higher lift with those durations.

 

100% would pick the high lift and if budget is a concern LS6/3 springs would be what I threw at it

 

Exactly the info I was looking for. Thank you for your expertise. High-lift it will be.

 

Thank you. Money isn't a huge concern for this build, but I already have upgraded beehive springs good to .560 with only 8k on them, so I'll prolly run those another 30k, and check 'em. Gonna take the heads to a local machine shop for a good cleanup and have them check for cracks, lap the valves, etc.

 

Might as well get them milled for a little compression bump while your at it. You'll need to verify pushrod length anyway with a new cam.

 

Does anyone know what the advertised seat to seat specs are? How do you know the intensity rating on the cam motion cams?, not calling you out I am just curious since I would like to know. I compared both cam specs, but what I am missing is the truck manifold intake runner length as well as the advertised duration:

It is showing about 5 ft lbs difference between the low and high lift at the peak. I also probably need a lot more reliable test of the factory L9H/L92 head flow as well.

 

Also I am not saying I am right and I would trust the what the more experienced members here said and I don't think the difference is that small, but like I said I am missing data that I need, like the saying always goes about garbage in or whatever it is. I am also missing the cross sectional areas of the intake and exhaust ports on the stock head and the intake manifold.

 

If you look up the CamMotion cams on SummitRacing they list both the advertised and .050" durations. From what I saw it was typically 55 (I did say "about" as it may not apply in all cases, but it does seem very consistent).

Here's the headflow https://ls1tech.com/forums/generatio...omparison.html

 

I think 55 is a close estimate. I’ll find out when I talk to them to change my order tomorrow. I’ll ask for a cam card that lists the advertised duration as well, and share it back here. They don’t have one on their website that I can find.