Comp Trunion failure....

[G8-4-Speed]

http://ls1tech.com/forums/generation-iv-internal-engine/1608865-comp-trunion-upgrade-failure-check-yours-3.html

Just to prove there are no guarantees when "Hot-Rodding".....

[Greg@PacePerformance]

I'm pretty sure he was using the "Summit" brand trunnion kit for $99.00 and not the Comp kit. I'm not sure there is a difference but there might be.

[LS1_Disciple]

I'm pretty sure he was using the "Summit" brand trunnion kit for $99.00 and not the Comp kit. I'm not sure there is a difference but there might be.

I understood that the OP in that thread (DietCoke) was using the Comp kit. He called Comp and even sent the trunions back to Comp to have them checked. He does show a picture of the Summit version to show how much bigger the retaining clips are than the Comp version. Does make me curious about mine now...

[Greg@PacePerformance]

Ahh I was going from memory when I ran across that thread a while back.

[Chewy]

I asked Livernois to quote me doing this mod when all the other work was being done and they don't recommend them. They said they'd had a couple fail.

[jcmGT]

wasn't there a revision to the trunion kit? I recall reading about it, google failing me at this moment.

[norm8332]

As I posted over there maybe it's the gritty residue that comes on them, only half of mine were cleaned because I discovered it too late. I did lube them on assembly though. I'm going to pull one from each side and compare..

[donkeyGT]

I asked Livernois to quote me doing this mod when all the other work was being done and they don't recommend them. They said they'd had a couple fail. Hmmm..I was going to have them do this when they do my DOD delete cam package..probably not now.

[vert]

I did mine when I changed out cams and they seemed to better quality than the stock trunions. I'm not too concerned about it.

[joemomma]

I asked Livernois to quote me doing this mod when all the other work was being done and they don't recommend them. They said they'd had a couple fail.

I have the Comp Trunion's and Livernois installed them! :uhm: I guess I should pull the covers and take a look! :)

[Chewy]

I saw everyone here doing them so I asked. Andy said they/he didn't recommend it. ????


Sent from my miniaturizer via tap dancing...

[-Ray-]

I did mine. If anyone remembers I did a full write up.

[I12XLR8]

I think I used your write up to install mine. I put them in as they were supposed to be more reliable than the stockers. I guess I could have saved a few hours and now some grey hairs?


Sent from my iPhone using Tapatalk

[KenV]

So much for cheap insurance. I guess it could happen with any rocker though.

The guy mentioned his cam specs: "251/259 .670 lsl/lsl 7400 limiter but typically shifts 7150-7200" Holy crap. That's asking a lot from a stock rocker IMHO.

[shane]

Had a set in the g8 zero issues and a set in the 240... hope this helps.

[Rawyzf]

I have them also, no issues as of yet. Thanks for the added worries though :p

[G8-4-Speed]

I didn't start the thread to make a panic, but the trunion upgrade can be just like changing lifters. There have been plenty of cases where guys deleted their DoD lifters just to have a LS7 lifter fail and have to pull the heads again. Some get carried away over-engineering their builds just trying to avoid possible failures. Nothing is bullet-proof....

[Andy@Livernois]

I can tell you that there is only 1 rocker we have had zero failures on, and that is the factory stock rocker. EVERY aftermarket rocker we have used has failed (or, in the case of jesel, or TDM are too heavy for hydraulic roller use). Every rocker upgrade we have used has failed. Yet in over 10 years of working on LS applications we have never seen a failure on the stock rocker regardless of usage. Only the 97-98 rockers have been a problem (like almost everything in the 97-98 engines).

[Chewy]

I didn't start the thread to make a panic, but the trunion upgrade can be just like changing lifters. There have been plenty of cases where guys deleted their DoD lifters just to have a LS7 lifter fail and have to pull the heads again. Some get carried away over-engineering their builds just trying to avoid possible failures. Nothing is bullet-proof....

This is what I was trying to do which is why I like to ask a "professionals" opinion.

[G8V8]

What about the photos of the needles failing out the OEM trunions?

[G8-4-Speed]

This is what I was trying to do which is why I like to ask a "professionals" opinion.

Livernois is correct, stock rockers work great! Plus they have done as many cam installs or more than anyone......

Who someone calls a "professional" is still an opinion......There are a good number of shops that can't tune but are still considered to have a "professional" opinion about tuning since they do it for a living...Do you homework and hope you have a good "BS" filter for what some post on forums whether it is a result, fix, or problem. Unfortunately, most don't talk about when they don't have a problem, mainly when they do. Spotting a trends and being able to identify the cause or specific issue to the trend is the trick. Too many theory's and not enough real fixes or results....Some problems are people generated vs part. Lifter noise after a cam swap can be people(mechanic) or part related. "You need these new rocker trunions to fix the noise" How well do you trust your mechanic???? Alto clutch pack was supposed to be the best upgrade going for the A6. Why? because it is new and cool and I got a Hundred on the shelf that I need to sell and can pawn off any failure on whoever I sold it to as a installer error.....JUNK. More "professional" BS...Please flush the toilet, it is full of money....

Find someone you like and will stand behind what they do, already did what you want, and can reproduce it......when you spend money, look for satisfaction but know there are no guarantees in "Hot-Rodding". Anything can break, anything can go wrong.

If we had a "Fail-Blog" for all the mechanic stuff that went wrong and all the money wasted, you'd walk.....a mistake on the wrong shoe is cheaper to fix..

[G8-4-Speed]

Sales pitch........
Failures aren't always the parts fault. Over-revving a motor or not having enough spring pressure or heavy valvetrain can be the cause of the problem. You start bouncing the valvetrain like a basketball and it is like detonation to a piston when using nitrous......Not saying that is why a rocker would break but it is something to think about.

[Chewy]

Livernois is correct, stock rockers work great! Plus they have done as many cam installs or more than anyone......

Who someone calls a "professional" is still an opinion......There are a good number of shops that can't tune but are still considered to have a "professional" opinion about tuning since they do it for a living...Do you homework and hope you have a good "BS" filter for what some post on forums whether it is a result, fix, or problem. Unfortunately, most don't talk about when they don't have a problem, mainly when they do. Spotting a trends and being able to identify the cause or specific issue to the trend is the trick. Too many theory's and not enough real fixes or results....Some problems are people generated vs part. Lifter noise after a cam swap can be people(mechanic) or part related. "You need these new rocker trunions to fix the noise" How well do you trust your mechanic???? Alto clutch pack was supposed to be the best upgrade going for the A6. Why? because it is new and cool and I got a Hundred on the shelf that I need to sell and can pawn off any failure on whoever I sold it to as a installer error.....JUNK. More "professional" BS...Please flush the toilet, it is full of money....

Find someone you like and will stand behind what they do, already did what you want, and can reproduce it......when you spend money, look for satisfaction but know there are no guarantees in "Hot-Rodding". Anything can break, anything can go wrong.

If we had a "Fail-Blog" for all the mechanic stuff that went wrong and all the money wasted, you'd walk.....a mistake on the wrong shoe is cheaper to fix..

Yeah, I've been on this earth and on forums in several capacities for enough years to filter out the guys that think they're right and the guys that ARE right or have proof. You, Pat G, Charlie, & Livernois are 4 of the big ones that come to mind. I like to listen to people that have done more than one or two builds and have proof of their work. ;)

Thanks for all the help you give all of us here. It's appreciated!!

[jcmGT]

Can you clarify this? I too have been considering doing this based on reports of the needle ending up in the oil pan. Would like to know if "rocker failure" is intended as the arm itself or the rocker arm assm, including trunion bearing.


I can tell you that there is only 1 rocker we have had zero failures on, and that is the factory stock rocker. EVERY aftermarket rocker we have used has failed (or, in the case of jesel, or TDM are too heavy for hydraulic roller use). Every rocker upgrade we have used has failed. Yet in over 10 years of working on LS applications we have never seen a failure on the stock rocker regardless of usage. Only the 97-98 rockers have been a problem (like almost everything in the 97-98 engines).

[Andy@Livernois]

What about the photos of the needles failing out the OEM trunions?

every failure we have seen has appeared to be from inadequate springs which cause valve float or improper pushrod pre-load (which can also cause unloading or severe loading of the rocker).

[G8V8]

Rick, Andy,
Good to know. So, do you feel that if propper springs, clearances and rev limits are maintained, the Comp Trunion "upgrade" is less, more or about equally likely to fail as the stock rocker trunions? The one shown in the LS1 thread seems to have had a hard life given the high revs it was subjected to. I have to wonder if a stock trunion would have also failed given equal abuse.

[Andy@Livernois]

Rick, Andy,
Good to know. So, do you feel that if propper springs, clearances and rev limits are maintained, the Comp Trunion "upgrade" is less, more or about equally likely to fail as the stock rocker trunions? The one shown in the LS1 thread seems to have had a hard life given the high revs it was subjected to. I have to wonder if a stock trunion would have also failed given equal abuse.


Personally, I feel they are a downgrade. No offense to them but GM spent (more than likely) millions of dollars figuring out the rocker arms and durability on the bearings. The aftermarket has a nasty habit of looking at a part and saying, "hey, we can make this for it". So they do, and cross their fingers that it's good. Again a 0% failure rate on the stock part versus a 100% failure rate on aftermarket parts (regardless of make).

[Chewy]

^^^^^I can't argue with that thinking.^^^^^

[screaminChick-n]

I have also heard the recomendation about only using stock gm lifters. So if i were to upgrade to 1.85 rockers on my LS3 with correct springs and rods , what lifters would you go with ? I have been told that the CTSV lifters fare pretty good. Some also suggested LS7 lifters ? Are these GM lifters better in some way than the LS3 lifters that come in the GXP?
I would like to hear your guys opinions - Andy@Livernois, Pat G, Rick@G8-4-speed, Charlie.........

[Andy@Livernois]

I have also heard the recomendation about only using stock gm lifters. So if i were to upgrade to 1.85 rockers on my LS3 with correct springs and rods , what lifters would you go with ? I have been told that the CTSV lifters fare pretty good. Some also suggested LS7 lifters ? Are these GM lifters better in some way than the LS3 lifters that come in the GXP?
I would like to hear your guys opinions - Andy@Livernois, Pat G, Rick@G8-4-speed, Charlie.........

LS7 lifters are the same as LS3 lifters. I do not, not, not recommend doing rockers on these, even with a stock camshaft. The CTS-Vr lifter is good for high RPM race use, but I would rather use an LS7 lifter in a street car.

[gtp6515]

What is the recommended max rpm for our modded motors with stock bottom ends. I think I am shifting right at 6500.

[Andy@Livernois]

We typically never spin past 6900 on any of our builds. Usually 6800 is our max unless it has our 2rmaxx cam, then it's 6900.

[gtp6515]

I have the livernois dual springs and ls7 lifters. You can spin the stock rotating assembly that high?

[Andy@Livernois]

6800 would be no issue so long as you have the proper camshaft to make power there.

[thebeast]

I doin the d1 and Livernois stage 1c cam to 6750