MTPZ06

Are you talking about pad on the rocker tip...like this? https://www.corvetteforum.com/forums...post1591588140

If you're talking about shimming or adjusting for proper wipe pattern...can't be done.

corvettenutz

Yes the pad on the tip. Makes sense to me.

corvettenutz

I emailed the guy that does this . I think im gonna send mine in.

Apocolipse

Just keep this in mind: GM LS7 stage 3 cam is 0.630" lift.

REDZED2

.630 and under is the standard for factory rocker geometry/ side loading and proper wipe pattern. Why do you think these new LS7 Cam Motion cams are .630/.612 lift on all of them?

http://www.cammotion.com/camshafts/ls7-camshafts/

Because they know their stuff.

Any of these cam are a good street and or strip grind and will get you in the 10's with ease with other bolt on's.

Apocolipse

Their titan line goes over 630 but thats prob because its more towards builds that understand constant valvetrain maintenance requirements and do not mind rebuilding heads every so often.

BigVette427

Do the lobes play a factor in this issue with the rocker arms maximum lift? Softer lobes from say CamMotion or TSP vs. say the Comp Lobes on one of those Lingenfelter cams; I would imagine the harder lobes would exacerbate the limit of rocker arm lift limit?

Bad_AX

I don't think this is true strictly speaking. Assuming the OEM head and valve train components are manufactured correctly, the maximum theoretical lift is closer to .650". As we know from the vast amount of user experience posted in CF and other forums, there can be numerous issues with the execution of the design which compromise the system when operating outside of the OEM lift. Yes, the majority of Cam Motion LS7 cams are intended to be used with the stock rockers and the .630" lift going to keep the phone from ringing.

The design of the lobes has nothing to do with the maximum achievable lift. At max lift, the rocker, valves, and springs don't know what the actual geometry of the cam lobes is.

The term "softer lobes" is technically meaningless, as is the assumption that Comp Cams only makes one type of LS cam lobe and it's "bad" compared to the lobes of other cam grinders. A cam lobe is only one element of a complex system and viewed in isolation is completely meaningless. There are a whole $hit load of LS7 cams available and off the top of my head, I can only think of 5 that have been tested on a Spinton as part of a complete system and operate with a very high level of stability past the 7000 rpm redline. Katech sells three of those cams. It's also worth pointing out that Comp grinds the Katech cams. This is not to say that other cams won't work successfully, but without paying to have a system tested, it's a roll of the dice.

BigVette427

I think you misunderstood my comments about the Lingenfelter Comp lobes; I wasn't implying that all Comp lobes are hard on your valvetrain, but whatever the Comp lobes are on the Lingenfelter grinds (GT19/21 or even GT17,) they will tear your valvetrain apart if you run it hard. Use Comp endurance lobes like LSL or LXL lobes and even at the same lift, it's a different story. There is a big difference in how the lobe opens/closes the valves especially on an LS motor. I suggest anyone looking into a cam needs to ask/know who's actually grinding the cams and what type of lobes they are using. Look for lobes designed specifically for LS engines.

"Soft lobes" is an accurate term when used to describe how the lobes are designed to open/close the valves; "soft" as in the wear on your valvetrain, not to be confused with the actual surface Ra of the lobes (ex. a 5150 vs 8620 core.) Using lobes specifically designed for LS motors makes all the difference in the world: they make power where you want it with less overall stress on the valvetrain (i.e. less valve spring pressure required for control,) and even do so in a quieter manner. On an LS7, that difference is all the more so important.

Bossdog

Baker Engineering said their cam/lobe design has been tested on the Spintron to 8500 rpm. I'm told most of their cams ground by Comp Cams. I didn't know if that was one on your list.

REDZED2

Quote:
[Originally Posted by wantbluC6 View Post
.630 and under is the standard for factory rocker geometry/ side loading and proper wipe pattern. Why do you think these new LS7 Cam Motion cams are .630/.612 lift on all of them?
I don't think this is true strictly speaking. Assuming the OEM head and valve train components are manufactured correctly, the maximum theoretical lift is closer to .650". As we know from the vast amount of user experience posted in CF and other forums, there can be numerous issues with the execution of the design which compromise the system when operating outside of the OEM lift. Yes, the majority of Cam Motion LS7 cams are intended to be used with the stock rockers and the .630" lift going to keep the phone from ringing.]

True, many run I have seen up to .660 on stock rockers. Doesn't mean longevity is in your future. .630 is the safe standard. Talked to several top builders I won't name. They are big names. I wouldn't run personally over .640. To each his own.

REDZED2

[QUOTE=Bad_AX;1595854722]I don't think this is true strictly speaking. Assuming the OEM head and valve train components are manufactured correctly, the maximum theoretical lift is closer to .650". As we know from the vast amount of user experience posted in CF and other forums, there can be numerous issues with the execution of the design which compromise the system when operating outside of the OEM lift. Yes, the majority of Cam Motion LS7 cams are intended to be used with the stock rockers and the .630" lift going to keep the phone from ringing.]




True and I know of what you speak. I still stand by my opinion of my last miss quoted post. Just what makes me feel comfortable for my own engine.

Bad_AX

I don't disagree with your position. While maximum theoretical lift of the LS7 rocker arm is stated to be 0.6567" by an OEM racing program manager, the cam I purchased for my own build is .636"/.641" lift on Comp LSG lobes. This is as far as I am willing to go with the OEM rocker, and I am having the rocker pallets trued and polished to reduce friction and potential binding.