Comp "r" yay or nay
01-08-2006, 01:02 AM
#1
Comp "r" yay or nay I have a brand new set of comp "r" lifters that i was going to put in my motor ive checked several forums and checked with comp from what im understanding the bad wrap is people using non udjustable valve train on the LSx series motors and that what cause the lifter failure if anyone has had a problem with these lifters with a LTx style motor with adjustable valve train please let me know.Also ive done a search and i cant find any pics of the old style and new style comp "r" clips that retain the lifter together link me a pic or where to get on to determine if the lifters i have are old or new style the guy that i bought them from had them laying around for awhile
01-08-2006, 01:17 AM
#2
nay from me. this is on an ls1 based motor.
i have the comp r's with the proper length pushrod to get me about .020 preload and my vavle train is LOUD. i called comp and they told me the problem was not having the adj rockers so i spent some big money on the rockers and pushrods and set it all up corectly to .008 or whatever it was they told me to and it was still loud. i tried from .008 up to about .050 preload and no matter what they were still loud. worse yet the motor would not rev past 5500rpm. i dont know what that was about but i am not the only one to have that problem.
i have the comp r's with the proper length pushrod to get me about .020 preload and my vavle train is LOUD. i called comp and they told me the problem was not having the adj rockers so i spent some big money on the rockers and pushrods and set it all up corectly to .008 or whatever it was they told me to and it was still loud. i tried from .008 up to about .050 preload and no matter what they were still loud. worse yet the motor would not rev past 5500rpm. i dont know what that was about but i am not the only one to have that problem.
01-08-2006, 02:19 AM
#3
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Originally Posted by parish8
nay from me. this is on an ls1 based motor.
i have the comp r's with the proper length pushrod to get me about .020 preload and my vavle train is LOUD. i called comp and they told me the problem was not having the adj rockers so i spent some big money on the rockers and pushrods and set it all up corectly to .008 or whatever it was they told me to and it was still loud. i tried from .008 up to about .050 preload and no matter what they were still loud. worse yet the motor would not rev past 5500rpm. i dont know what that was about but i am not the only one to have that problem.
i have the comp r's with the proper length pushrod to get me about .020 preload and my vavle train is LOUD. i called comp and they told me the problem was not having the adj rockers so i spent some big money on the rockers and pushrods and set it all up corectly to .008 or whatever it was they told me to and it was still loud. i tried from .008 up to about .050 preload and no matter what they were still loud. worse yet the motor would not rev past 5500rpm. i dont know what that was about but i am not the only one to have that problem.
fuerzaws6
01-08-2006, 06:36 PM
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I had the Comp R's in my heads/cam LT1 T/A.. I ran them for a year or so without any problems at all. And I ragged the total **** out of my car every day that I drove it.. My rev limiter was set at 6900 for a long time and it would beat the rev limiter to death without any problems.. That was 3 years ago so it was the older style I guess..
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01-08-2006, 07:52 PM
#9
Originally Posted by 1QuickT-A
I had the Comp R's in my heads/cam LT1 T/A.. I ran them for a year or so without any problems at all. And I ragged the total **** out of my car every day that I drove it.. My rev limiter was set at 6900 for a long time and it would beat the rev limiter to death without any problems.. That was 3 years ago so it was the older style I guess..
AFR and MTI both recommended comp R when using dual valve springs and high ramp cams.
01-09-2006, 07:28 AM
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Yeah....Comp Rs and Pro Magnum rockers here...work fine for 2 years and 7k hard miles...no issues at all. Perfect. .010" preload cold. Soak them in oil overnight after you clean them.
01-09-2006, 07:22 PM
#14
Originally Posted by SAM98WS6
Yeah....Comp Rs and Pro Magnum rockers here...work fine for 2 years and 7k hard miles...no issues at all. Perfect. .010" preload cold. Soak them in oil overnight after you clean them.
Hell I have 20000 more miles then that with stock valvetrain, no issues either
01-09-2006, 08:09 PM
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From all my research i have determined that comp may have some quality issues with these lifters. I had mine set perfect and they croaked on me, so obviously some work and some dont.
I would not let them even get 15 feet away from my motor, it might break thinking about having them in it!
I would not let them even get 15 feet away from my motor, it might break thinking about having them in it!
01-10-2006, 09:05 AM
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Same here, setup with proper cold pre-load with adjustable t&d shaft rockers. A roller shaft just backed out of the lifter and kaboom. I will follow up with some quotes I posted on another board.
01-10-2006, 09:07 AM
#18
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"Being the subject of much ridicule on these i've done quite a bit of research and have a few comments. First off it would appear that not enough preload was put on these as the clips where hammered out of the lifter either by the pushrod itself or the spring cup constantly banging against the retainer clip (underneath the retainer clip) as it will be loaded and unloaded every time the cam comes onto the lobe and up off the base circle and then back off the lobe onto the base circle. I think the pre-load spec range that have to be followed with these lifters according to comp are simply rediculous at .002-.004, that's an awfully small range of acceptability. I find it even funnier as an aluminum block/aluminum head combo will expand more so then a iron block/aluminum head or iron block/iron head combo. I would say that makes it imparative that these lifters pre-load are set hot. Jason at thunder recommended .008-.010 to me cold.
Now that being said there have also been many instances in where the roller shaft just backs out of the damn lifter, which happened to myself, Geoff at thunder racing (although his customer was lucky cause the shaft remained in the lifter casing until he pulled the lifter in which the lifter shaft just simply fell out in his hand, he was boggled at how it didn't happen in the motor), and quite a few other ls1tech members. This to me is more along the lines of poor quality control, maybe like the same quality control issues they had with the 918 springs. This may serve to suggest why some have failures and some don't, outside of the incorrectly set up valve train ofcourse.
Some other things to consider are that these lifters don't really seem to add any advantage over a standard replacement lifter from what I seem to be following. For instance, the lsk lobe which is one of the most agressive you'll see on a hydraulic roller (yes, some solid lobes are used on hydraulics but not typically and are obviously more agressive then the lsk) which thunder racing is having so much success with are using the stock lifters with comp 921 shimmed within .050" from coil bind. They are carying out to 7000rpm too. These 921 generate some big big pressure for a stock pocket spring. I don't think the patriot, or crane come even close as far as their stock pocket ls1 spring goes on pressure.
If you really insist on replacing your lifters with something that is better then stock and will supposedly handle more rpm and bigger spring pressure i'd seriously consider the Morels. Some may suggest the Lunati as well but it is somewhat unclear as if the morel and lunati lifter are the same pieces. Erik @ HPE thought they were and I can't remember who right off the top of my head but another popular tech builder saw some differences and suggested they may not be the same lifter.
Anyway, just my opinion"
Now that being said there have also been many instances in where the roller shaft just backs out of the damn lifter, which happened to myself, Geoff at thunder racing (although his customer was lucky cause the shaft remained in the lifter casing until he pulled the lifter in which the lifter shaft just simply fell out in his hand, he was boggled at how it didn't happen in the motor), and quite a few other ls1tech members. This to me is more along the lines of poor quality control, maybe like the same quality control issues they had with the 918 springs. This may serve to suggest why some have failures and some don't, outside of the incorrectly set up valve train ofcourse.
Some other things to consider are that these lifters don't really seem to add any advantage over a standard replacement lifter from what I seem to be following. For instance, the lsk lobe which is one of the most agressive you'll see on a hydraulic roller (yes, some solid lobes are used on hydraulics but not typically and are obviously more agressive then the lsk) which thunder racing is having so much success with are using the stock lifters with comp 921 shimmed within .050" from coil bind. They are carying out to 7000rpm too. These 921 generate some big big pressure for a stock pocket spring. I don't think the patriot, or crane come even close as far as their stock pocket ls1 spring goes on pressure.
If you really insist on replacing your lifters with something that is better then stock and will supposedly handle more rpm and bigger spring pressure i'd seriously consider the Morels. Some may suggest the Lunati as well but it is somewhat unclear as if the morel and lunati lifter are the same pieces. Erik @ HPE thought they were and I can't remember who right off the top of my head but another popular tech builder saw some differences and suggested they may not be the same lifter.
Anyway, just my opinion"
01-10-2006, 09:08 AM
#19
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"I mean it will unload when there is slack in the valve train which will be during the time the lifters is on the base circle of the cam if the valve train is not set up properly (with lash) which maybe the cause of the issues above. Unless something is chaotic (i.e. like .600" lash which would be pretty rediculous) then the lifter will be loaded when the lifter gets to the actual lobe of the cam up off the base circle and unloaded again when the lifter gets back on the base circle off the lobe of the cam.
As far as the rest of your statement we're pretty much on the same page. Also, one thing to note is the use of non-stock rockers REAL SHAFT (not harland sharps or yella terras) with different pivot lengths. Rockers like T&D (what I had), comp shaft rockers (which are pretty identical to T&D), and jessel. These may induce even more load on the lifter as it will be harder for the lifter to push up against the rocker arm as the pushrod cup is often brought closer to the fulcrum and the pivot length is changed to maintain the 1.7 ratio. Further, they may induce valve float as they will lift the valve quicker and faster then an equal ratio stock rocker because of the pivot length difference and stiffer body.
I'd also stay away from the non real shaft rockers I indicated above. I have personal experience with the harland sharps removing 2 mph from my car everything else being equal when I was running my 230/236 cam. The problem with them seems to be that the cradle that the stock rockers used is removed which is an excellent guide to reduce deflection in the stock rocker arms. Furthermore, I believe stock small block chevy rocker studs are 3/8" and am pretty sure big block rocker studs are 7/16". The ls1 rocker stud is 8mm which is closest to 5/16" which will deflect more then the bigger sizes obviously which will become an issue when you remove the stock rocker cradle and don't replace it with a real shaft rocker system and it's cradle."
As far as the rest of your statement we're pretty much on the same page. Also, one thing to note is the use of non-stock rockers REAL SHAFT (not harland sharps or yella terras) with different pivot lengths. Rockers like T&D (what I had), comp shaft rockers (which are pretty identical to T&D), and jessel. These may induce even more load on the lifter as it will be harder for the lifter to push up against the rocker arm as the pushrod cup is often brought closer to the fulcrum and the pivot length is changed to maintain the 1.7 ratio. Further, they may induce valve float as they will lift the valve quicker and faster then an equal ratio stock rocker because of the pivot length difference and stiffer body.
I'd also stay away from the non real shaft rockers I indicated above. I have personal experience with the harland sharps removing 2 mph from my car everything else being equal when I was running my 230/236 cam. The problem with them seems to be that the cradle that the stock rockers used is removed which is an excellent guide to reduce deflection in the stock rocker arms. Furthermore, I believe stock small block chevy rocker studs are 3/8" and am pretty sure big block rocker studs are 7/16". The ls1 rocker stud is 8mm which is closest to 5/16" which will deflect more then the bigger sizes obviously which will become an issue when you remove the stock rocker cradle and don't replace it with a real shaft rocker system and it's cradle."
01-10-2006, 09:15 AM
#20
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You know..I used these parts without issue...but if I was doing it again I would use something else and not risk it...obviously making these exact valvetrain components work properly is not easy.
I would use Morels and jesel if I had the money and wouldnt use stock if they were the last parts on earth.
I would use Morels and jesel if I had the money and wouldnt use stock if they were the last parts on earth.