Trunnion Bearings breaking in LS2 GTO
Thread Starter
Staging Lane
Joined: Feb 2013
Posts: 53
Likes: 0
From: MO
Trunnion Bearings breaking in LS2 GTO Folks, I'm starting to have a recurring problem with my Goat. My LS2 is eating trunnion bearings. I have the comp upgraded set, stock rockers, stock lifters, and a PRC .675 spring set with around 20k miles on it. Pat G Custom cam (227/230 .614/.609 111+2 LSA) is the cam. The cam has been in the car for 40,000 miles, and there were no problems til a month ago. The car hasnt been driven any different, and if anything it has been driven more conservatively with the majority of the miles being highway miles.
A month ago, when it started ticking and we found the first broken trunnion bearing, I had my builder check the springs and they were fine. We replaced the bearing and it was fine. The ticking went away and everything. Then, about a week ago, the ticking returned, so we took off the valve covers, and sure enough, 2 more bearings were broken. Has anyone seen or heard of this happening? We are going to go ahead and fix it, however, just replacing them isnt solving the root issue.
No one around here has heard of them going bad, much less 3 of them.
Any thoughts? Oiling problems? Lifters?
__________________
A month ago, when it started ticking and we found the first broken trunnion bearing, I had my builder check the springs and they were fine. We replaced the bearing and it was fine. The ticking went away and everything. Then, about a week ago, the ticking returned, so we took off the valve covers, and sure enough, 2 more bearings were broken. Has anyone seen or heard of this happening? We are going to go ahead and fix it, however, just replacing them isnt solving the root issue.
No one around here has heard of them going bad, much less 3 of them.
Any thoughts? Oiling problems? Lifters?
__________________
So are you saying that some of the bearing that you just replaced broke?
Also which springs do you have PRCs or Comp Cams?
Have you made any changes in the oil you're running ?
Also which springs do you have PRCs or Comp Cams?
Have you made any changes in the oil you're running ?
Last edited by 99Bluz28; Mar 19, 2013 at 12:43 AM.
Maybe it's the higher opening spring rates of the PRC .675" EHT dual valve springs combined with 40k miles on them that has worn them out.
PRC .675" EHT Open Spring Pressure: 450 lb. @ .600" lift
I run the same cam except 111+3 lsa, and PAC 1521 dual springs.
PAC 1521 Open Spring Pressure: 372 lb. @ .600" lift.
PRC .675" EHT Open Spring Pressure: 450 lb. @ .600" lift
I run the same cam except 111+3 lsa, and PAC 1521 dual springs.
PAC 1521 Open Spring Pressure: 372 lb. @ .600" lift.
Comp trunions are JUNK
http://lsxnation.net/forum/showthrea...-you-comp-cams
http://lsxnation.net/forum/showthrea...our-f-trunions
https://ls1tech.com/forums/generatio...eck-yours.html
Go CHE bushes, or leave them stock. Spread the gospel, avoid comp trunions like the plague. The only thing worse then those pieces of crap is the customer service you get when you try to get them to make it right.
http://lsxnation.net/forum/showthrea...-you-comp-cams
http://lsxnation.net/forum/showthrea...our-f-trunions
https://ls1tech.com/forums/generatio...eck-yours.html
Go CHE bushes, or leave them stock. Spread the gospel, avoid comp trunions like the plague. The only thing worse then those pieces of crap is the customer service you get when you try to get them to make it right.
I'm rebuilding an engine that had the Comp Trunions fail. It seems like several started binding real hard, while one just completely came apart and dumped a bunch of debris into the engine. The Comp lifters were even damaged with the retaining clip beat out and the cup just fumbling around loose. The dowel pin on the single bolt cam was even bent.
Another shop had done the work, so I'm not sure if the Trunions were installed incorrectly or what. I'm not saying Comp made a poor product, but there are some who have no problems with them at all and some who do.
Another shop had done the work, so I'm not sure if the Trunions were installed incorrectly or what. I'm not saying Comp made a poor product, but there are some who have no problems with them at all and some who do.
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Teching In
Joined: Jul 2011
Posts: 41
Likes: 0
From: Pacific WA
im also interested in the cost of the CHE setup. oh man 420. but i guess its worth it so you dont have to worry
Last edited by autogeek23; Mar 19, 2013 at 11:39 AM. Reason: information has been updated in comments above
Thread Starter
Staging Lane
Joined: Feb 2013
Posts: 53
Likes: 0
From: MO
Ah. I hadnt heard of them failing. I was a bit surprised, as I had heard Comp made good stuff.
Most likely I will be upgrading to some roller rockers that are pre-assembled in the very near future, then.
Most likely I will be upgrading to some roller rockers that are pre-assembled in the very near future, then.
