Straub Bushing Trunion Kits?
I fully expect "some" gold in the pan, but only a fine powder/color at best. (and very little)
I have rebuilt gear boxes at work that have bronze babbitt bushing/bearings where they have 24/7/300+ days a year runtime.
Yes, issues occur when the oil is low or even the wrong type as some oils don't have the additives and will eat/attack the bronze.
The needle bearings that encapsulate a LS stock rocker arm do not rotate 360* like needle bearings that encapsulate a lifter axle. Two totally different applications. The same needles are loaded over and over again with a stock LS rocker arm versus a roller lifter that "rolls" and allows the bearings to rotate 360*.
There are many manufacturers that now sell roller lifters that utilize a bushing to encapsulate the axle on a roller lifter. They are using bushings because they spread the load out over a larger surface area and thus can handle much more spring pressure and RPM. They are superior to a needle bearing in this aspect which is why using a bushing to encapsulate a LS rocker arm trunion is a better idea. Since that bearing or bushing is loaded over and over again, it is better to use a bushing that spreads that load out over a larger amount of area and doesn't concentrate load in a smaller amount of surface area as seen in Kurt's pictures.
I would be willing to bet that if you were to examine the trunions on a street/strip engine with moderate valve lift and duration and one that has over 10K miles you'd see very similar wear. The physics involving that wear doesn't change no matter if it's a street/strip application or a road course application. Yes the road course engine may have more high RPM cycles, but the load is still similar and still concentrated in the same area.
I'll let Kurt give his experiences with street/strip type engines and not try to put the cart too far in front of the horse, but I am willing to bet he has seen the same wear in less demanding applications.
So where does this statement about 360* of rotation come from?
So where does this statement about 360* of rotation come from?
The Best V8 Stories One Small Block at Time
My machine shop recommended the OE rockers with the OE bearings and trunnions. This is on my 418 LS3 with heavy double springs, stainless valves, and high lift cam.
I ran this info by them and they said I can do whatever I want, but they have more problems with other internal part failures than they do with the rockers and trunnions.
In their opinion the OE needles fail due to lake of maintenance and high mileage.
IDK, part of me wants to jump on the wagon and get me some, other part says heck with it. If I'm going to be pulling the rockers off and inspecting them every 5 to 10k miles I may as well use the OE bearings and just replace them every 20k or so. Just do it like part of a tune up. Suppose I could just plan on doing it every winter when the car is down. Not that difficult, and really not that expensive.
My other concern about the bushings is the difference in friction. Seems like the bushings would create more friction than rollers.
Again, I don't know. Just thinkin.
My machine shop recommended the OE rockers with the OE bearings and trunnions. This is on my 418 LS3 with heavy double springs, stainless valves, and high lift cam.
I ran this info by them and they said I can do whatever I want, but they have more problems with other internal part failures than they do with the rockers and trunnions.
In their opinion the OE needles fail due to lake of maintenance and high mileage.
IDK, part of me wants to jump on the wagon and get me some, other part says heck with it. If I'm going to be pulling the rockers off and inspecting them every 5 to 10k miles I may as well use the OE bearings and just replace them every 20k or so. Just do it like part of a tune up. Suppose I could just plan on doing it every winter when the car is down. Not that difficult, and really not that expensive.
My other concern about the bushings is the difference in friction. Seems like the bushings would create more friction than rollers.
Again, I don't know. Just thinkin.
Just curious,
I went with the Straub bushings after reading through this thread, but how many miles do have you put on them since install? Is it a cruiser or strip car? No one so far has put down what kind of wear or miles they've put on since their install that I'm aware of.
I did use the GM install procedure to install this kit, I will report back when I get 3000 miles on the kit, I'll pull the valve covers and check the wear on a few bushings.
your I did use the GM install procedure to install this kit, I will report back when I get 3000 miles on the kit, I'll pull the valve covers and check the wear on a few bushings.
















