comp r lifters
Originally Posted by warp_6
+1. You will need to use adjustable rocker arms. Use your checker to find zero lash. That will be the length of your new push rods. Then you will set your pre-load with the rockers.
Originally Posted by moeZ28
I have Comp R lifters with stock rocker arms...0.020" preload and never had a problem with them. My car is very quiet compared to most that sound like sewing machines.
Originally Posted by jegten
how would i set the preload with the rockers when i am using the stock rocker arms? and torquing them to 22lbs?
Originally Posted by warp_6
It would be better to use adjustable rockers. I guess you could add .025 to your zero lash push rod length (zero lash w/ checker 7.350) + .025 = 7.375 new push rod length, but I wouldn't go anymore than that. That still is much more pre-load than they call for, but some are running .025 -.050. and aren't having any problems. If you are going to try to apply the .002-.004 pre-load with a push rod I don't see it happening (zero lash w/checker 7.350) + .003 = 7.353 new length.
thanks for this info.
i am wanting to keep my stock rockers, and still be able to use the comp r.
i see how the small preload might not have an effect in figuring the length of pr. any suggestions?
thanks
PS: i guess i can always sell these lifters and get the 850s.
Last edited by jegten; Mar 30, 2007 at 12:55 AM.
I would use adjustable rockers if you are going to use the comp R's. That way you can cotrol precisly how much pre-load your lifters get. Or like you say sell the R's, and get something else. Myself I am setting up some R's right now. I just ordered the PR's tonight. I am using comp shaft mount adj. rockers. If you do go the adj. rocker route. You will need to clearance your valve covers. It seems every mod you make creats some other problem, or something else that needs to be worked out. Putting out fires.
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Verdad Gallardo thanks, guys.
i guess i got a little insecure after seeing the almost "negligible" effect the .002-.004 would have in the formula to figure out the pr length. so, i suppose i would do the warm up thing, go back to zero lash, add the .003 to that new zero lash in the formula, and order my new pr, if need be. right?
i really appreciate this.
hey, brad, like your numbers a lot, what is your set up?
i guess i got a little insecure after seeing the almost "negligible" effect the .002-.004 would have in the formula to figure out the pr length. so, i suppose i would do the warm up thing, go back to zero lash, add the .003 to that new zero lash in the formula, and order my new pr, if need be. right?
i really appreciate this.
hey, brad, like your numbers a lot, what is your set up?
Originally Posted by jegten
thanks, guys.
i guess i got a little insecure after seeing the almost "negligible" effect the .002-.004 would have in the formula to figure out the pr length. so, i suppose i would do the warm up thing, go back to zero lash, add the .003 to that new zero lash in the formula, and order my new pr, if need be. right?
i really appreciate this.
hey, brad, like your numbers a lot, what is your set up?
i guess i got a little insecure after seeing the almost "negligible" effect the .002-.004 would have in the formula to figure out the pr length. so, i suppose i would do the warm up thing, go back to zero lash, add the .003 to that new zero lash in the formula, and order my new pr, if need be. right?
i really appreciate this.
hey, brad, like your numbers a lot, what is your set up?
Heres my setup https://ls1tech.com/forums/dynamometer-results-comparisons/685582-dynoed-my-new-head-cam-forged-motor-today.html
TECH Resident
Joined: Jan 2003
Posts: 855
Likes: 0
From: AUSTIN TX
Originally Posted by brad8266
Why are you guys telling him to preload those lifters to .025 when Comp says to preload them to .002-.004? Use the checker and just order a custom rod if need be.
Yeah it may not be a problem now, but by running 6 times the recommended preload those lifters will collapse and fail much earlier than they would if they were preloaded properly. The excuse that its ok because they work now is retarded.
Its simple to acheive proper preload by using different size PR's alone. You just use a PR checking tool and measure zero lash and then add preload and thats what size PR you need. It takes like 5 minutes to do, where do you get these times from.
So what about the variances, they are there regardless so you might as well get your parts ordered as close as possible to what they should be. And even if you did check each lifter for its individual proper PR length it would take like what an hour?
Thats not much time to get it right the first time.
Its simple to acheive proper preload by using different size PR's alone. You just use a PR checking tool and measure zero lash and then add preload and thats what size PR you need. It takes like 5 minutes to do, where do you get these times from.
So what about the variances, they are there regardless so you might as well get your parts ordered as close as possible to what they should be. And even if you did check each lifter for its individual proper PR length it would take like what an hour?
Thats not much time to get it right the first time. TECH Resident
Joined: Jan 2003
Posts: 855
Likes: 0
From: AUSTIN TX
Originally Posted by brad8266
Yeah it may not be a problem now, but by running 6 times the recommended preload those lifters will collapse and fail much earlier than they would if they were preloaded properly. The excuse that its ok because they work now is retarded.
I agree 100%
Its simple to acheive proper preload by using different size PR's alone. You just use a PR checking tool and measure zero lash and then add preload and thats what size PR you need. It takes like 5 minutes to do, where do you get these times from.
No it is NOT.
So what about the variances, they are there regardless so you might as well get your parts ordered as close as possible to what they should be. And even if you did check each lifter for its individual proper PR length it would take like what an hour? Thats not much time to get it right the first time.
I agree 100%
Its simple to acheive proper preload by using different size PR's alone. You just use a PR checking tool and measure zero lash and then add preload and thats what size PR you need. It takes like 5 minutes to do, where do you get these times from.
No it is NOT.
So what about the variances, they are there regardless so you might as well get your parts ordered as close as possible to what they should be. And even if you did check each lifter for its individual proper PR length it would take like what an hour?
Thats not much time to get it right the first time.
Originally Posted by BOWTIE
With a conventional hydraulic lifter "as close as possible" is fine, with a Comp R or solid lifter it is not. Why do you think the first line in Comp Cams requirement for these lifters is that you must have an adjustable valvetrain for proper use of these lifters.
I have comp R's and I guess the shop that put my motor together did not know not to use stock rockers. My lifters are loud as hell. I order new Cadillac lifters but they are on B/O. I am pretty sure I have 7400 length pushrods in the car now. Would it by wise to go to a 7350 or 7325 until I put my new lifters in? If someone had to guess what would be the best size standard pushrod to use on stock rockers?
Kane
Kane
Originally Posted by Kaneman
I have comp R's and I guess the shop that put my motor together did not know not to use stock rockers. My lifters are loud as hell. I order new Cadillac lifters but they are on B/O. I am pretty sure I have 7400 length pushrods in the car now. Would it by wise to go to a 7350 or 7325 until I put my new lifters in? If someone had to guess what would be the best size standard pushrod to use on stock rockers?
Kane
Kane
Stock 6.0 heads on an Iron block 408 not sure on the thickness of the head gaskets. It is a small cam 220 224 581 581 114 lsa. I will see if I can get a pushrod measurer I was just trying to get something close. I realize there are so many variables.
Thanks,
Kane
Thanks,
Kane
