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As they are a very new development, I understand that there is little, if anything, known about these kits. If anyone knows anything about them or even has some scientific input as to whether or not using a bushing rather than a needle bearing in the design seems like a good one, please do tell. I am going to be going with either these or the comp trunion upgrade in the next few months, and I am trying to decide between the two.
IMO they're better because with the bushing the load is spread out over a much larger area.
Loading those same few needle bearings over and over again is going to put more wear and tear on the part than with the bushing that spreads that same load out over a much larger surface area.
Not only that, the trunions themselves in the bushing kit are REM polished for reduced friction and better lubricity.
IMO they're better because with the bushing the load is spread out over a much larger area.
Loading those same few needle bearings over and over again is going to put more wear and tear on the part than with the bushing that spreads that same load out over a much larger surface area.
Not only that, the trunions themselves in the bushing kit are REM polished for reduced friction and better lubricity.
I think they're the cat's meow personally!
Good deal. I appreciate the input! Is there much of a difference in longevity of this design. Vs that of a needle bearing type? If I were to get a set, it would be going on a car that spends the vast majority of its time on the street.
What is your opinion on them compared to comp's, BTR's, etc..., Martin?
This is what happens with the Comp and BTR kits....
If you've ever looked at an aftermarket rocker, you'll see that the trunnion is very tightly fit to the body of the rocker arm, this keeps a bath of oil at the bearings so they're constantly lubricated, but with the factory rocker the trunnion has huge gaps on either side and the trunnion & needle bearings don't get proper lubrication. The rough surface finish on the Comp/BTR kits doesn't help either, but it didn't wear because of a lack of hardness, I tested a bunch of them on our rockwell tester.
This is what happens with the Comp and BTR kits....
If you've ever looked at an aftermarket rocker, you'll see that the trunnion is very tightly fit to the body of the rocker arm, this keeps a bath of oil at the bearings so they're constantly lubricated, but with the factory rocker the trunnion has huge gaps on either side and the trunnion & needle bearings don't get proper lubrication. The rough surface finish on the Comp/BTR kits doesn't help either, but it didn't wear because of a lack of hardness, I tested a bunch of them on our rockwell tester.
So, with all the hundreds...maybe thousands of people that have the BTR kit or the Comp kit, there would be post after post on here about their failures and everybody would be saying to go to aftermarket rockers.
Exactly how often does this actually happen and under what circumstances?
So, with all the hundreds...maybe thousands of people that have the BTR kit or the Comp kit, there would be post after post on here about their failures and everybody would be saying to go to aftermarket rockers.
Exactly how often does this actually happen and under what circumstances?
It doesn't exactly "fail" - it's just wearing and putting metal into your motor - I've seen this with the half dozen sets of the roller bearing style upgrade kits that I've taken apart that had any significant time on them....it's a systemic problem. The trunnion would need a hard wear sleeve like the factory setup has to eliminate this issue with the aftermarket bearing kits.
It doesn't exactly "fail" - it's just wearing and putting metal into your motor - I've seen this with the half dozen sets of the roller bearing style upgrade kits that I've taken apart that had any significant time on them....it's a systemic problem. The trunnion would need a hard wear sleeve like the factory setup has to eliminate this issue with the aftermarket bearing kits.
Does the use of a bushing instead of a bearing avoid this issue? That picture frightens me a bit because I plan on putting some miles on the car!
Does the use of a bushing instead of a bearing avoid this issue? That picture frightens me a bit because I plan on putting some miles on the car!
I use bushed rockers in many rocker arm systems in a lot of different street and race motors including small and big block Mopars and FE Fords from Hughes Performance, Comp, Crane, and Precision Oil Pumps....it's a proven street/race system that shows very minimal wear after tens of thousands of miles, I've taken motors apart that we built 10-15 years ago and the bushed rockers were still within spec. Additionally, the bushing material won't hurt your motor like steel will. Like has been said before, there's more load bearing capacity due to the extra load bearing surface, plus the oil holes in the trunnion do a lot to solve the problem that I talked about with the body to trunnion fit being way to loose to create a bath of oil over the bearings.
The move to bushed roller lifters in recent years is another example of the manufacturers seeing that it's a superior system for load bearing capacity, needle bearings are always failing in solid roller lifters with high spring pressures.
I use bushed rockers in many rocker arm systems in a lot of different street and race motors including small and big block Mopars and FE Fords from Hughes Performance, Comp, Crane, and Precision Oil Pumps....it's a proven street/race system that shows very minimal wear after tens of thousands of miles, I've taken motors apart that we built 10-15 years ago and the bushed rockers were still within spec. Additionally, the bushing material won't hurt your motor like steel will. Like has been said before, there's more load bearing capacity due to the extra load bearing surface, plus the oil holes in the trunnion do a lot to solve the problem that I talked about with the body to trunnion fit being way to loose to create a bath of oil over the bearings.
The move to bushed roller lifters in recent years is another example of the manufacturers seeing that it's a superior system for load bearing capacity, needle bearings are always failing in solid roller lifters with high spring pressures.
It doesn't exactly "fail" - it's just wearing and putting metal into your motor - I've seen this with the half dozen sets of the roller bearing style upgrade kits that I've taken apart that had any significant time on them....it's a systemic problem. The trunnion would need a hard wear sleeve like the factory setup has to eliminate this issue with the aftermarket bearing kits.
Sorry...I do not buy that. That picture along with the problem you show looks more like there was no oil to the top end of the motor or the material wasn't hardened correctly. As I stated, if this were a huge issue, there would be posts all over here telling people not to use the factory rockers and trunnion upgrade kits.
If you already have the BTR or Comp upgrade kit, I would not be running out to replace it anytime soon. If you haven't done it, then look at the bushing option. Stating the bearing kits are all going to fail is just bogus if that is what you are implying...especially since nobody has any real wear data on these kits per Martin Smallwoods post earlier.
Sorry...I do not buy that. That picture along with the problem you show looks more like there was no oil to the top end of the motor or the material wasn't hardened correctly. As I stated, if this were a huge issue, there would be posts all over here telling people not to use the factory rockers and trunnion upgrade kits.
If you already have the BTR or Comp upgrade kit, I would not be running out to replace it anytime soon. If you haven't done it, then look at the bushing option. Stating the bearing kits are all going to fail is just bogus if that is what you are implying...especially since nobody has any real wear data on these kits per Martin Smallwoods post earlier.
Don't buy it then, I'm just simply stating the facts as I have seen them as a engine builder who has used these parts for many years, the material was hardened properly as per our big Rockwell hardness tester in both core hardness and surface hardness, and like I said - lubrication is the issue which I explained in my post about the inability of the stock rocker to create an oil bath above the bearing like aftermarket rockers are set up to do. I actually have real world experience with dozens of these sets, you're just guessing and don't want to believe someone who has spent excessive time looking into this issue.
Let's not forget that rods have bushings in them. They are not pressure fed oil either. If someone could put roller bearings in them and make them live and make .5% more power they would sell a million.
Let's not forget that rods have bushings in them. They are not pressure fed oil either. If someone could put roller bearings in them and make them live and make .5% more power they would sell a million.
Let's not forget that rods have bushings in them. They are not pressure fed oil either. If someone could put roller bearings in them and make them live and make .5% more power they would sell a million.
Only time they have issues is a lack of oil.
Tim
Interesting that I recently saw an engine rebuild (can't remember manufacturer but it was foreign) where there was a cup at the top of the pushrod and a ball bearing (single) sat within the cup to interface with the rocker arm. Had never seen that before.
Interesting that I recently saw an engine rebuild (can't remember manufacturer but it was foreign) where there was a cup at the top of the pushrod and a ball bearing (single) sat within the cup to interface with the rocker arm. Had never seen that before.
Very common setup with Chryslers due to the extreme angles between the rocker and pushrod they would have a tendency to spit push rods if it was a ball-ball style. We use the ball-cup rocker arms from Crane and Hughes on all performance Chryslers because the Comp setup sucks as you have to preload the lifters to .010" of dry lash to keep them from popping out.
02-01-2016, 02:36 PM
Straub Bushing Trunion Kits? 
