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That looks like a variation on the CHE kit, at least the "free floating bushing" aspect of things, but those trunnions look like that only support 40-50% of the bushing. Is that picture messed up?
Anything manufactured by Manton is high end...and yes, floating trunnions in contact with the loaded part of the assembly, other part retain fresh oil...
Christian
It seems that the more discussions about these trunnions that are posted here, as well as the more articles I read about them, it gets even more confusing. The only thing that everyone seems to agree on, is that the OE design is less than ideal, and POSSIBLY could cause problems...........
It seems that the more discussions about these trunnions that are posted here, as well as the more articles I read about them, it gets even more confusing. The only thing that everyone seems to agree on, is that the OE design is less than ideal, and POSSIBLY could cause problems...........
Hi leadfoot,I personally not agree.
The OEM GM LS1/LS6 Rockers/trunnion are perfect for some couple of 100K miles when they are used the way GM intent to...
When someone installs aftermarket valvetrain parts, the reliability becomes the concern of this someone plus his aftermarket provider of parts.
Solutions are existing, some cheap and some more expensive...and the trunnions are a part of the entire valvetrain assembly balance.
Christian
It seems that the more discussions about these trunnions that are posted here, as well as the more articles I read about them, it gets even more confusing. The only thing that everyone seems to agree on, is that the OE design is less than ideal, and POSSIBLY could cause problems...........
The OE design may not necessarily be more prone to failing, but what is certain is that if they do fail the needle bearings spilling out will destroy your engine. If you’re adding additional stress over stock it’s a no brainer to upgrade as insurance.
The OE design may not necessarily be more prone to failing, but what is certain is that if they do fail the needle bearings spilling out will destroy your engine. If you’re adding additional stress over stock it’s a no brainer to upgrade as insurance.
Hi Lowcountry, the difficulty is to upgrade, when most the aftermarket products for that application are a downgrade...
Christian
This post may not sit well with some, but it is truth. I had an early set of AFR 225 heads, back in late 2004. The valve springs were installed at 1.700" installed height. This is nearly .100" TOO SHORT, and VERY stiff. I also had REV dual valvesprings. I ran standard LS6 trunnions/rockers. In 30,000 miles, I never had any issue with the stock trunnions needles coming out, or any issues, period. FF 10 years, and I "upgraded" to the Comp kit. I should've left the LS7 trunnions in. Biggest POS in my built LS7. I'd never buy anything from Comp again. Period. IMHO, too bad they ran Crane out of business..... .
This post may not sit well with some, but it is truth. I had an early set of AFR 225 heads, back in late 2004. The valve springs were installed at 1.700" installed height. This is nearly .100" TOO SHORT, and VERY stiff. I also had REV dual valvesprings. I ran standard LS6 trunnions/rockers. In 30,000 miles, I never had any issue with the stock trunnions needles coming out, or any issues, period. FF 10 years, and I "upgraded" to the Comp kit. I should've left the LS7 trunnions in. Biggest POS in my built LS7. I'd never buy anything from Comp again. Period. IMHO, too bad they ran Crane out of business..... .
And I'm quite sure that you realized that as soon as you pressed out the OE trunnions and needles, there's no turning back........
This conversation is somewhat reminiscent of the 4 bolt main versus 2 bolt main debate before the LS engines gained popularity. There were 2 bolt main big blocks and small blocks racing everyday at the strip. The so-called inferior 2 bolts main engines often held up quite well, and were plentiful and cheap.
The 2 bolt blocks were fine for their designed purpose, and often able to withstand far more power than intended. The C5 stock trunnions seem to be fine for their designed purpose, and can far exceed those specifications.
Still, we should also accept that aftermarket cam lift and increased spring demands likely exceed the design, especially at higher rpm’s. The transition point from stock to next level is often blurry, but exists nonetheless.
This conversation is somewhat reminiscent of the 4 bolt main versus 2 bolt main debate before the LS engines gained popularity. There were 2 bolt main big blocks and small blocks racing everyday at the strip. The so-called inferior 2 bolts main engines often held up quite well, and were plentiful and cheap.
The 2 bolt blocks were fine for their designed purpose, and often able to withstand far more power than intended. The C5 stock trunnions seem to be fine for their designed purpose, and can far exceed those specifications.
Still, we should also accept that aftermarket cam lift and increased spring demands likely exceed the design, especially at higher rpm’s. The transition point from stock to next level is often blurry, but exists nonetheless.
Well stated! The problem is, since many of us are "car nuts", and cannot stand the thought that there might be some part in our car that is anything less than 100% reliable, annoys us no end. Therefore, we tend to want to fix things that may not yet be broken......and we then fall into the trap of our fixes simply creating other issues for us.
Just as a side note, for what it's worth, my engine is noticeably quieter with the Straub bushings in place, compared to the OE or Comp Cams trunnions.
Probably due to them floating on an oil film rather than the direct connection of roller bearings.
Originally Posted by leadfoot4
Just as a side note, for what it's worth, my engine is noticeably quieter with the Straub bushings in place, compared to the OE or Comp Cams trunnions.
Probably due to them floating on an oil film rather than the direct connection of roller bearings.
Most likely, but that would possibly also reaffirm that my bronze bushings do not have any excess clearance, or "wobble issues", as the valvetrain is very quite.....much quieter that it was in the stock condition (or, for that matter, with the Comp Cams trunnions).
Most likely, but that would possibly also reaffirm that my bronze bushings do not have any excess clearance, or "wobble issues", as the valvetrain is very quite.....much quieter that it was in the stock condition (or, for that matter, with the Comp Cams trunnions).
The bronze material of your trunnions bushings will tame the frequencies related to the impact valve closing, and that is good, but doesn't mean there is no wear of the trunnions...
Christian
The bronze material of your trunnions bushings will tame the frequencies related to the impact valve closing, and that is good, but doesn't mean there is no wear of the trunnions...
Christian
Point for bronze! On the other hand, bronze seems to be more dependent on good oiling (which is questionable at high rpm with a stock oil pump)…
Hi vette4fl'
There are different types of bronze that can be used in that application, from cheap to expensive, and the CHE one is certainly the most expensive because that form of bronze works in that application.
I did try to obtain info from the bronze used by other manufactory and I couldn't...
Christian
Hi vette4fl'
There are different types of bronze that can be used in that application, from cheap to expensive, and the CHE one is certainly the most expensive because that form of bronze works in that application.
I did try to obtain info from the bronze used by other manufactory and I couldn't...
Christian
Smith Bros is C932. I believe that is an industry standard for bronze bushings. Other than that, I do not know anything about that hardness being good or whatever.
Straub, BTR, and others sell this model. Some market it under their own brand name.
CHE’s website states: ”CHE has developed its own proprietary material that has revolutionized the industry by setting a new standard for wear and performance.”
Clear as mud!
Last edited by vette4fl; Mar 12, 2022 at 02:51 PM.
CHE’s website states: ”CHE has developed its own proprietary material that has revolutionized the industry by setting a new standard for wear and performance.”
Clear as mud!
Hi vette4fl,
I understand why when you initiate an R&D you do not "give" your results...
I have stored in my garage a set of LS1/LS6 CHE rocker installed by them with 40K miles, revving daily at 7500rpm ++, and they still look like new...yes when I bought the set, they were sounding like expensive to me, not anymore!
Christian
Well, the whole trunion bushing thing escalated to say the least. Found an obliterated lifter on the #2 exhaust, which sent metal in the motor. I’m in no way trying to do the bare minimum with the fixes - and out the motor came. I found cylinders 1 and 2 had some scratches that could be felt with a finger nail, so I’m praying the machine shop can save the block. It’s there currently and shouldn’t need much beyond that - the crank is getting ground, bore / hone, and everything else measured within GM spec when I checked. It seems like metal made its way into the oil for sure. It’s all entirely my fault for enjoying the car a “little too much”…..but building a motor is an absolute blast and I got to dig out all of my mics, calipers, stretch gauges etc. to blueprint it when it’s reassembled (hopefully).
They should at least throw us a bone. Certs has “Retsin”! Chevron has “Techron”!
Four out of five dentists recommend….
Originally Posted by miami993c297
Hi vette4fl,
I understand why when you initiate an R&D you do not "give" your results...
I have stored in my garage a set of LS1/LS6 CHE rocker installed by them with 40K miles, revving daily at 7500rpm ++, and they still look like new...yes when I bought the set, they were sounding like expensive to me, not anymore!
Christian
I know this is an old thread and I'm not trying to revive it...just put in my 2 cents. I also ran into this problem with Smith brothers trunnions. What lead me to suspect something was my oil analysis. After installing the kit, the oil report was showing higher accumutions of copper and tin...basically bronze. This lead me to inspect the trunnions and found the same issue. They were wearing uneven and had bad wobble when seating on the pedestal. The tolerance was done. I called BTR since I bought the kit from them and they told me that there was nothing they can do....I didn't wanted my money back since it has been more than 6 months of ownership, just wanted to give them feedback. Their reply was, "call trh manufacturer " so I did. I contacted Smith Brothers and explained what happened. I got the most stubborn and condescending reply, and was told that I do not know what I was talking about and I was doing something wrong. Additionally, I tried leaving feedback on the vendor website but was deleted.
With all this said, Smith Brothers trunnions are a waste of money!!!
I know this is an old thread and I'm not trying to revive it...just put in my 2 cents. I also ran into this problem with Smith brothers trunnions. What lead me to suspect something was my oil analysis. After installing the kit, the oil report was showing higher accumutions of copper and tin...basically bronze. This lead me to inspect the trunnions and found the same issue. They were wearing uneven and had bad wobble when seating on the pedestal. The tolerance was done. I called BTR since I bought the kit from them and they told me that there was nothing they can do....I didn't wanted my money back since it has been more than 6 months of ownership, just wanted to give them feedback. Their reply was, "call trh manufacturer " so I did. I contacted Smith Brothers and explained what happened. I got the most stubborn and condescending reply, and was told that I do not know what I was talking about and I was doing something wrong. Additionally, I tried leaving feedback on the vendor website but was deleted.
With all this said, Smith Brothers trunnions are a waste of money!!!
I will keep my original designed GM Needle bearings and If and when one fails simply flush engine and install a new GM rocker.
The failure rate of the originals is Highly over hyped in my opinion. My originals are still running strong in my engine even after I had to rebuild the engine due to a Failed rod bearing 115,000 miles on them now.
