Solid roller lifters......
12-09-2014, 09:29 AM
#81
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My point is, regardless of what the bushing material is, even if it has zero friction, the shear of the oil in such close tolerances could be sufficient to cause the roller to slide up the ramp, especially in high lift aggressive cams that most of us are running. There is so much side load on the roller and the roller contact area is so small compared to the bearing area that it may be easier for the roller to slide up the ramp than roll over it. My concern is mainly when the oil is cold. It would not be out of the ordinary for me to pull the boat out in 40 or 50 degree weather with water temps in the upper 30's or low 40's. My 20w50 Amsoil is going to be just a little thicker than when it hits 200+. If bushings are the best thing since sliced bread, why are engine builders going to needles on cams? Not to diverge, but my 14,000 rpm 2 cycles were all needles on everything, granted when they went, it was catastrophic.
12-09-2014, 09:45 AM
#82
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My point is, regardless of what the bushing material is, even if it has zero friction, the shear of the oil in such close tolerances could be sufficient to cause the roller to slide up the ramp, especially in high lift aggressive cams that most of us are running. There is so much side load on the roller and the roller contact area is so small compared to the bearing area that it may be easier for the roller to slide up the ramp than roll over it. My concern is mainly when the oil is cold. It would not be out of the ordinary for me to pull the boat out in 40 or 50 degree weather with water temps in the upper 30's or low 40's. My 20w50 Amsoil is going to be just a little thicker than when it hits 200+. If bushings are the best thing since sliced bread, why are engine builders going to needles on cams? Not to diverge, but my 14,000 rpm 2 cycles were all needles on everything, granted when they went, it was catastrophic.
