Custom L&M Intake Cam change results:

Dashti

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Awesome, is it worth it swapping to your cam from Comp cams?
I have stage 3 on intake and stage 1 on exhaust
 
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Shaun@AED

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Awesome, is it worth it swapping to your cam from Comp cams?
I have stage 3 on intake and stage 1 on exhaust

The goal here was not to out-power the Comp 3's, but to match the power output at RPM without losing any low/midrange and allowing for stock springs without valve float.
 

466roller

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So the "NSR" isn't exactly accurate in their description? Have you had cars on the dyno that have experienced valve float with the comps? Did they have power fall off in the upper RPM?
 

Shaun@AED

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So the "NSR" isn't exactly accurate in their description? Have you had cars on the dyno that have experienced valve float with the comps? Did they have power fall off in the upper RPM?

I suppose that depends on the intended RPM band Comp had in mind.

We have seen valve float above 7600RPM with their Stage 3 setup on the coyote and stock valve springs. A buddy bent his exhaust valves from banging on the 8K rev limiter in his 14. Another customer in the middle east bent the exhaust valves as well. As a result I set the rev limits with Comp Cams lower than with stock cams unless valve springs are installed.

According to L&M the data he has on the Comp lobe profiles vs stock spring shows they will float the valves. They are too aggressive on the lobe profile for higher RPM. The intake lobe also floats, but due to where it floats (bounces on the seat) we've not seen it tap the piston and bend the valve. The exhaust closes during the overlap phase so it does get close enough to the piston to tap it.
 

burke985

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So on a boosted coyote running say 8.5ish psi and e85 with a TVS what do you think the gains would equal over the stock set. Probably would also need a fuel system upgrade also I assume if your running a BAP....just curious :) , seems this would be a nice addition to help up top with us TVS guys
 
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Shaun@AED

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So on a boosted coyote running say 8.5ish psi and e85 with a TVS what do you think the gains would equal over the stock set. Probably would also need a fuel system upgrade also I assume if your running a BAP....just curious :) , seems this would be a nice addition to help up top with us TVS guys

Hard to say exactly. I guess we should try the swap on your car? :)
 

burke985

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Hard to say exactly. I guess we should try the swap on your car? :)


Hmmm.... so tempting was dead set on fuel system next gonna have to think about it lol. Just did the opg and crank sprocket feels so much better with that peace of mind. I will definitely let you know
 

oldbones

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Are these cams regrind? Will they need shim to set the lash?

Maybe this fall I'll try a set. The baby cj are good, but i want a little more power on motor.
 

Dashti

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I suppose that depends on the intended RPM band Comp had in mind.

We have seen valve float above 7600RPM with their Stage 3 setup on the coyote and stock valve springs. A buddy bent his exhaust valves from banging on the 8K rev limiter in his 14. Another customer in the middle east bent the exhaust valves as well. As a result I set the rev limits with Comp Cams lower than with stock cams unless valve springs are installed.

According to L&M the data he has on the Comp lobe profiles vs stock spring shows they will float the valves. They are too aggressive on the lobe profile for higher RPM. The intake lobe also floats, but due to where it floats (bounces on the seat) we've not seen it tap the piston and bend the valve. The exhaust closes during the overlap phase so it does get close enough to the piston to tap it.

I agree because my friend bent an exhaust valve with Comps 3 and destroyed his motor
 

torchred02gt

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Are these cams regrind? Will they need shim to set the lash?

Maybe this fall I'll try a set. The baby cj are good, but i want a little more power on motor.

I'm about to install that exact set up with my ported boss/accufab combo. I'll let you know how it runs.
 

Shaun@AED

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Was he running limiters? I'd guess probably not

Limiters have no effect on valve float. They simply limit the amount of advance/retard.
It's not cam timing that causes the valves to hit the pistons, it's float. We can see it in data logs, cams become erratic bouncing around the commanded cam timing. They don't go off in one direction to max advance/retard.
 
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466roller

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Limiters have no effect on valve float. They simply limit the amount of advance/retard.
It's not cam timing that causes the valves to hit the pistons, it's float. We can see it in data logs, cams become erratic bouncing around the commanded cam timing. They don't go off in one direction to max advance/retard.

I understand limiters don't effect valve float. I was wondering if the cams are not limited and someone got a little to aggressive with the cam timing and say swung the exhaust cam a little too far could that not cause bent exhaust valves?
What about before the RPM patch was available and the cams would revert back to "0" ? Could this be a contributing factor?
Sorry I know this is getting a little off topic of the post and I hope your not taking offense. I think we all appreciate you sharing a small portion of your experience and insight into this
 

torchred02gt

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I understand limiters don't effect valve float. I was wondering if the cams are not limited and someone got a little to aggressive with the cam timing and say swung the exhaust cam a little too far could that not cause bent exhaust valves?
What about before the RPM patch was available and the cams would revert back to "0" ? Could this be a contributing factor?
Sorry I know this is getting a little off topic of the post and I hope your not taking offense. I think we all appreciate you sharing a small portion of your experience and insight into this

It's a mechanical issue. Not a vct issue. The ramp rates and lift of the camshafts themselves are too aggressive for stock valve springs at 7,600+rpm causing the stock valve springs to let the valve float as they don't have enough spring pressure to properly operate.
 

milas

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How would this compare to a full set of Comp Cam stage 1?

Do I read it right that this intake is good for 5hp? How would that gain compare to Comp Cam stage 1 with AED tuning?

Sent from my SM-G900P using Tapatalk
 

Shaun@AED

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How would this compare to a full set of Comp Cam stage 1?

Do I read it right that this intake is good for 5hp? How would that gain compare to Comp Cam stage 1 with AED tuning?

Sent from my SM-G900P using Tapatalk

No, we gained 17HP over the Boss intake cams. It should be around 20HP over GT cams.
I have no accurate back to back comparison of Comp Stage 1 vs stock or any other setup so I cannot tell you what the difference would be.
 

milas

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Would the CJ baby cam for exhaust and LM Intake cam work well together, something close to Comp Cam Stage 3 but safer at high RPM?

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