Comp Cams Short-Travel Lifters?
#1
Comp Cams Short-Travel Lifters?
I've seen a couple of threads now where Mamo has used the Comp short travel lifter on his newer setups. I've also talked to Tooley who used modified LS7s with travel limiters in his personal build.
I'm going to need new lifters when I pull the heads (144k miles) and would like to go with the lifters that will not cause a ton of noise and that will actually work well with an LSL/LXL lobed cam with a lightweight valvetrain using stock rockers (TFS heads with turned down LS3 valves, Ti retainers, PM guides).
My question is: does anyone have any experience with these or limited travel setups? I know Morel is tossed around as one of the best and a link-bar setup would be nice. Comp also has a link-bar version of their short travel lifter, but is priced comparable to the Morels.
I've seen a lot of poor reports with the LS7 around failures and a lot of noise related issues. Tooley also did some spintron testing and this is what he told me for the LS7s:
"In the spintron testing we did the lifters actually bled down worse at idle, and then lofted at high RPM if spring pressure wasn't sufficient. We saw .100"-.150" of lifter bleed down from cycle to cycle at low rpm, pretty shocking if you ask me."
I'm always willing to spend what is needed to make the car as reliable as I can make it, but $500+ for Comp or Morels vs $130 LS7s or $200 Comp 850s makes me wonder if I'd be okay with the 850s or LS7s with travel limiters and a drilled LS2 lifter tray vs Comp or Morel link bar lifters...
Thanks.
I'm going to need new lifters when I pull the heads (144k miles) and would like to go with the lifters that will not cause a ton of noise and that will actually work well with an LSL/LXL lobed cam with a lightweight valvetrain using stock rockers (TFS heads with turned down LS3 valves, Ti retainers, PM guides).
My question is: does anyone have any experience with these or limited travel setups? I know Morel is tossed around as one of the best and a link-bar setup would be nice. Comp also has a link-bar version of their short travel lifter, but is priced comparable to the Morels.
I've seen a lot of poor reports with the LS7 around failures and a lot of noise related issues. Tooley also did some spintron testing and this is what he told me for the LS7s:
"In the spintron testing we did the lifters actually bled down worse at idle, and then lofted at high RPM if spring pressure wasn't sufficient. We saw .100"-.150" of lifter bleed down from cycle to cycle at low rpm, pretty shocking if you ask me."
I'm always willing to spend what is needed to make the car as reliable as I can make it, but $500+ for Comp or Morels vs $130 LS7s or $200 Comp 850s makes me wonder if I'd be okay with the 850s or LS7s with travel limiters and a drilled LS2 lifter tray vs Comp or Morel link bar lifters...
Thanks.
#2
TECH Apprentice
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I used comp limited travel lifters for the first time, I have used morel street series (which are ls7 tie bar ) or plain LS7 lifters in all builds. bleed down at idle is not such a big issue.
I have found the LS7 lifters to be far the quietest lifter there is. Consistently. Just use a spring with around 160 on seat and 400 thou per inch and your right.
A friend of mine used comp lifters , his were quite noisy, however he ran 180 lb on seat with a 505 lb /inch rate. It seamed one or two were noisy the rest OK.
Same with this engine I just did. It has around 0 lash hot. I am going to try more preload, to kill the noise, however I am seriously thinking of just swapping them for LS7s and setting them up at 30-40 thou preload.
LS7 lifters are fine! Lack of spring pressure and loft kills lifters, needle rollers are not designed for that.! However a 1.3 inch spring will not load them enough for a failure!
I have found the LS7 lifters to be far the quietest lifter there is. Consistently. Just use a spring with around 160 on seat and 400 thou per inch and your right.
A friend of mine used comp lifters , his were quite noisy, however he ran 180 lb on seat with a 505 lb /inch rate. It seamed one or two were noisy the rest OK.
Same with this engine I just did. It has around 0 lash hot. I am going to try more preload, to kill the noise, however I am seriously thinking of just swapping them for LS7s and setting them up at 30-40 thou preload.
LS7 lifters are fine! Lack of spring pressure and loft kills lifters, needle rollers are not designed for that.! However a 1.3 inch spring will not load them enough for a failure!
#5
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^^^If u pull down a morel street series lifter, it is identical internal to the LS7 lifter. Have u checked that? I have! I can tell u for a fact they are same dimensions!!! You have to grind button off though to pull it down. All I ever use is the street series morels 99% of time. I make sure I know what is going in my motors!
So before u make statements be sure to check! As I can back it up!
The reason of the lifter failure is always related to spring pressure, or aggressive lobes, incorrect setup, ie correct install pressures, correct open pressures. I have never had a LS7 lifter fail! But I use good lobes and good setup. Even the cheaper morel lifters have failures. In fact any lifter will.
The biggest issue u get with any hyd lifter is bleed down. You need enough closed pressure to hold the weight, and you need enough open to control the valve yet prevent bleed down.
How many ppl set up correctly valve springs to 60 thou within bind? Also 160lb or so on seat and 400 open? This is the reason u get lifter loft, and lifter failure, its just a basic engineering fact.
Guys like Brian Tooley use them and quite a few more, it is more then "bad luck" more so incorrect installs.
To date never had a LS7 lifter fail! And I do cam swaps all the time! ! !
The link bar will save u spinning the lifter but will not prevent failure otherwise.
So before u make statements be sure to check! As I can back it up!
The reason of the lifter failure is always related to spring pressure, or aggressive lobes, incorrect setup, ie correct install pressures, correct open pressures. I have never had a LS7 lifter fail! But I use good lobes and good setup. Even the cheaper morel lifters have failures. In fact any lifter will.
The biggest issue u get with any hyd lifter is bleed down. You need enough closed pressure to hold the weight, and you need enough open to control the valve yet prevent bleed down.
How many ppl set up correctly valve springs to 60 thou within bind? Also 160lb or so on seat and 400 open? This is the reason u get lifter loft, and lifter failure, its just a basic engineering fact.
Guys like Brian Tooley use them and quite a few more, it is more then "bad luck" more so incorrect installs.
To date never had a LS7 lifter fail! And I do cam swaps all the time! ! !
The link bar will save u spinning the lifter but will not prevent failure otherwise.
Last edited by hymey; 11-12-2012 at 05:28 PM.
#6
Yeah, I'm going to do TFS As Cast heads prepped by Tooley (LS3 valves, PM guides, his Platinum springs 160/400 pressure) stock rockers with Comp Trunion upgrade, and 3/8" pushrods. The LS3 valve turned down is 83g vs 110 for the standard Ferrea. Stock LS1 valves are 100g.
I'll be running LSL/LXL lobe combination.
Properly setup, the LS7 lifter should be fine in there. Especially if I have Tooley modify them and install a travel limiter.
I'll be running LSL/LXL lobe combination.
Properly setup, the LS7 lifter should be fine in there. Especially if I have Tooley modify them and install a travel limiter.
#7
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^^^If u pull down a morel street series lifter, it is identical internal to the LS7 lifter. Have u checked that? I have! I can tell u for a fact they are same dimensions!!! You have to grind button off though to pull it down. All I ever use is the street series morels 99% of time. I make sure I know what is going in my motors!
So before u make statements be sure to check! As I can back it up!
The reason of the lifter failure is always related to spring pressure, or aggressive lobes, incorrect setup, ie correct install pressures, correct open pressures. I have never had a LS7 lifter fail! But I use good lobes and good setup. Even the cheaper morel lifters have failures. In fact any lifter will.
The biggest issue u get with any hyd lifter is bleed down. You need enough closed pressure to hold the weight, and you need enough open to control the valve yet prevent bleed down.
How many ppl set up correctly valve springs to 60 thou within bind? Also 160lb or so on seat and 400 open? This is the reason u get lifter loft, and lifter failure, its just a basic engineering fact.
Guys like Brian Tooley use them and quite a few more, it is more then "bad luck" more so incorrect installs.
To date never had a LS7 lifter fail! And I do cam swaps all the time! ! !
The link bar will save u spinning the lifter but will not prevent failure otherwise.
So before u make statements be sure to check! As I can back it up!
The reason of the lifter failure is always related to spring pressure, or aggressive lobes, incorrect setup, ie correct install pressures, correct open pressures. I have never had a LS7 lifter fail! But I use good lobes and good setup. Even the cheaper morel lifters have failures. In fact any lifter will.
The biggest issue u get with any hyd lifter is bleed down. You need enough closed pressure to hold the weight, and you need enough open to control the valve yet prevent bleed down.
How many ppl set up correctly valve springs to 60 thou within bind? Also 160lb or so on seat and 400 open? This is the reason u get lifter loft, and lifter failure, its just a basic engineering fact.
Guys like Brian Tooley use them and quite a few more, it is more then "bad luck" more so incorrect installs.
To date never had a LS7 lifter fail! And I do cam swaps all the time! ! !
The link bar will save u spinning the lifter but will not prevent failure otherwise.