Robust Trunion Upgrade. Data Speaks.
05-06-2017, 12:53 PM
#21
To date we have a little over 40K miles on 1 set of the bushing trunnions in a period of 16 months in a driving school corvette. I have several customers with over 10K miles on trunnion kits. I have airboat engine builder customer with over 300 hours on 4 LS3 engines with sustained 4400 rpm trips for 3 to 5 hours at a haul.
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05-06-2017, 02:29 PM
#22
Since we are all here on this subject, I'd like to know what kind of rockers are in the vette engines, if they are identical to the 5.3L truck rockers from the same years? Or better yet, what kind of rocker is in the LS6 engine, that supports the LS6 camshaft profile?
And: What is the longest duration OEM camshaft from any OEM engine that will fit a 5.3L gen3 engine, that also works with OEM 5.3L rockers?
And: What is the longest duration OEM camshaft from any OEM engine that will fit a 5.3L gen3 engine, that also works with OEM 5.3L rockers?
05-06-2017, 02:40 PM
#23
Your question is honestly better left for another thread but ill amswer it.
ALL ls rockers in the 4.8, 5.3, 5.7 ls1 and ls6, and 6.0l lq4 lq9 and ls2 are exactly the same. Furthermore the exhaust rocker arms on all rectangular port heads are the same as those gen3 rockers. The ls6 cam does not have an aggressive profile at all.
You are asking very rudimentary questions for an in depth thread.
The cams that will work in a 5.3l...that is hard to quanitfy. Gen3 5.3s have the cam pickup in the rear and the gen4 in the front off the cam gear. Further explaining what that means, a gen 4 cam (ls2 ls3 ls9 ls7 or any gen4 4.8 5.3 or 6.0) will not be a direct fit into a gen3. Alternately a gen3 cam is not a straight swap into every gen4. Some have vvt some have afm some have both THEN some have only a single bolt.
The ls6 is the largest gen3 cam that comes in a stock engine that will drop directly into a gen3 5.3. Above that the ls9 cam will BUT you will need about $200 in more parts to convert the cam pickup to the front instead of the rear. Ls7 wont work period.
Gm of course has "performance cams" but none came in stock engines. like the hot cam and asa cam. The asa cam is the largest that will fit BUT youll have to double check clearances to make sure.
There are ALOT better choices out there than any of them honestly. The ls6 cam is no longer available new. So thats a bad deal. The ls9 cam is. Its roughly $120. For not much more you can get a brand new billet core cam and make alot mor power with the same longevity.
ALL ls rockers in the 4.8, 5.3, 5.7 ls1 and ls6, and 6.0l lq4 lq9 and ls2 are exactly the same. Furthermore the exhaust rocker arms on all rectangular port heads are the same as those gen3 rockers. The ls6 cam does not have an aggressive profile at all.
You are asking very rudimentary questions for an in depth thread.
The cams that will work in a 5.3l...that is hard to quanitfy. Gen3 5.3s have the cam pickup in the rear and the gen4 in the front off the cam gear. Further explaining what that means, a gen 4 cam (ls2 ls3 ls9 ls7 or any gen4 4.8 5.3 or 6.0) will not be a direct fit into a gen3. Alternately a gen3 cam is not a straight swap into every gen4. Some have vvt some have afm some have both THEN some have only a single bolt.
The ls6 is the largest gen3 cam that comes in a stock engine that will drop directly into a gen3 5.3. Above that the ls9 cam will BUT you will need about $200 in more parts to convert the cam pickup to the front instead of the rear. Ls7 wont work period.
Gm of course has "performance cams" but none came in stock engines. like the hot cam and asa cam. The asa cam is the largest that will fit BUT youll have to double check clearances to make sure.
There are ALOT better choices out there than any of them honestly. The ls6 cam is no longer available new. So thats a bad deal. The ls9 cam is. Its roughly $120. For not much more you can get a brand new billet core cam and make alot mor power with the same longevity.
Last edited by tech@WS6store; 05-06-2017 at 02:48 PM.
05-08-2017, 11:05 AM
#28
TECH Resident
Why hasn't someone from Comp stepped up and replied to these threads? If I were them I would be all mover this negative feedback, after all we are some of their biggest customers...
05-08-2017, 11:58 AM
#29
What huge conglomerate like them actually posts? They have acct reps, but they are busy taking care of their accts. They rely on the big magazine builds, social media, and all their other advertising to get into a war on here.
They could prob tell you they still sell thousands of trunions a month. What would that really tell us though?
They could prob tell you they still sell thousands of trunions a month. What would that really tell us though?
05-08-2017, 02:23 PM
#30
TECH Senior Member
05-08-2017, 05:51 PM
#34
TECH Senior Member
I know, I was being facetious.... ;-)
05-11-2017, 09:53 PM
#36
I mentioned they were getting a bad reputation on LS1TECH and got the impression this website has an industry wide reputation like most enthusiasts sites of being a collection of clueless whiners, keyboard wizards and Internet drama Queens. Those are my words and perception not Comps. Several did say they had used the Comp Cams trunion kit on their own projects without issues.
I got the feeling at least a couple of reps thought some slander by the competition was involved in blowing any trunnion issues way out of proportion to the actual issues - most of which is installer errors. I've seen enough anti Comp Cams comments on this website that in my opinion were poorly supported in many cases to understand why a Comp Cams rep might think that.
Last edited by 99 Black Bird T/A; 05-11-2017 at 09:59 PM.
05-11-2017, 11:11 PM
#37
Last year when I was at the PRI show in Indy, I asked the Comp Cams reps about the CCams Trunion rocker arm issue. They genuinely looked surprised. What trunnion upgrade issue? They reply amounted to we've sold 10's of thousands of those trunnion upgrade kits an seldom heard of problems. All of the problems they were aware of the trunnion kits except one went back to installer error and failing to read or understand or follow the instructions.
A failure rate of 1% might sound pretty good unless you happened to be in that magic percentile. Even the tech from the WS6 store stated that "not all sets failed". That leads me to believe that the failure rate is quite a bit higher than 1%.
05-11-2017, 11:45 PM
#38
What is this all of a sudden, the main stream media? I was making a point to a guy saying they all fail. The fact is not all fail that is what i meant. I meant to clean up a generic and untrue statement. Im not defending them, but id rather have facts. I have no actual percentage of how many failed, and i have heard of none personally fail and seen none fail. Ive even asked customers to check theirs during a cam change, they showed no evidence of failing.
Ls1tech is a VERY small microcasm of the ls world. Just like all the other sites. Just like i said.
People normally only find stuff on the internet and post because something went wrong, not right.
Like i said, ask comp theyll prob tell you of the tens of thousands they sold this quarter. They have been around since 2009ish 2010 so there are so many more out there vs the few we have seen or heard of on here.
It very well could just be due to other issues like poor quality oil or oiling issues in general. Long intervals between oil changes etc assembling them with no lube, grease, oil and then starting them up relying on engine oil to lube them. The list goes on. At first there was a question on how far to install the bearing. That was clarified (mostly). But just installing dry doesnt help anything. Possibly even adding a break im additive like the licas zddp could help. Ive said a few of these things before as well.
They work for quite a few customer it seems. Enough so summit had to copy. Not sure if they are the same or not but not likely. They prey on the fact that people will buy what is cheaper no matter what and ignore inferior quality or craftsmanship. Then when it fails "i bought these comp trunions and they failed" is the story.
I have 1 set on an engine i am personally going to take apart. They have been on since 2010. Ill post my results in here and a few more threads when i do.
Ls1tech is a VERY small microcasm of the ls world. Just like all the other sites. Just like i said.
People normally only find stuff on the internet and post because something went wrong, not right.
Like i said, ask comp theyll prob tell you of the tens of thousands they sold this quarter. They have been around since 2009ish 2010 so there are so many more out there vs the few we have seen or heard of on here.
It very well could just be due to other issues like poor quality oil or oiling issues in general. Long intervals between oil changes etc assembling them with no lube, grease, oil and then starting them up relying on engine oil to lube them. The list goes on. At first there was a question on how far to install the bearing. That was clarified (mostly). But just installing dry doesnt help anything. Possibly even adding a break im additive like the licas zddp could help. Ive said a few of these things before as well.
They work for quite a few customer it seems. Enough so summit had to copy. Not sure if they are the same or not but not likely. They prey on the fact that people will buy what is cheaper no matter what and ignore inferior quality or craftsmanship. Then when it fails "i bought these comp trunions and they failed" is the story.
I have 1 set on an engine i am personally going to take apart. They have been on since 2010. Ill post my results in here and a few more threads when i do.
05-12-2017, 05:21 AM
#39
The previous comment on the improper hardness and heat treatment plus the statement that they have sold 10's of thousands makes me wonder. If only 25,000 units were sold with a failure rate of 1% that could lead to the failure of 250 engines built with the hard earned money of trusting people who put their faith in a product that had insufficient quality control checks or purchased from the lowest bidder or both.
A failure rate of 1% might sound pretty good unless you happened to be in that magic percentile. Even the tech from the WS6 store stated that "not all sets failed". That leads me to believe that the failure rate is quite a bit higher than 1%.
A failure rate of 1% might sound pretty good unless you happened to be in that magic percentile. Even the tech from the WS6 store stated that "not all sets failed". That leads me to believe that the failure rate is quite a bit higher than 1%.
I'm inclined to stick with Jesel or T&D or Yella Terra or stock rockers for LS rockers but that is based out of fear not data. One of my cars has lots 160,000 miles on stock rockers and 130,000 of that with heads and an XER cam. The rockers still look good. No issues to date. The other car has Jesel's because I wanted roller rockers.
