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Trunnion Bearings breaking in LS2 GTO

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Old Mar 18, 2013 | 11:39 PM
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Default 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?
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Old Mar 19, 2013 | 12:28 AM
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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 ?

Last edited by 99Bluz28; Mar 19, 2013 at 12:43 AM.
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Old Mar 19, 2013 | 12:41 AM
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No, trunnion bearings were swapped when the cam was swapped. no problems before.

PRC .675 springs
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Old Mar 19, 2013 | 02:46 AM
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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.
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Old Mar 19, 2013 | 06:14 AM
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I don't know, I'm still using the factory LS3 rockers with a Comp Cam 231 239 .617 .624 113.
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Old Mar 19, 2013 | 07:01 AM
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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.

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Old Mar 19, 2013 | 09:26 AM
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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.
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Old Mar 19, 2013 | 10:10 AM
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Anyone know how much the CHE setup costs and if it's a DIY setup or do you send in yours to have converted?
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Old Mar 19, 2013 | 10:56 AM
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Originally Posted by The Alchemist
Anyone know how much the CHE setup costs and if it's a DIY setup or do you send in yours to have converted?
You have to send them in to CHE.

It's 420 if you send in your own rockers and 620 if you want to buy them out right.
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Old Mar 19, 2013 | 11:30 AM
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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
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Old Mar 19, 2013 | 11:32 AM
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Interesting...
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Old Mar 19, 2013 | 04:30 PM
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The big boys in big blocks (Crower, Isky) have both gone to bushings in their lifters and it's worked out very well for them so far. Glad to see it's an option on these rockers.
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Old Mar 19, 2013 | 05:05 PM
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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.
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