It's like a "TIME BOMB" inside your engine, "Ticking" it's way to that unhappy moment when you least expect it. Occurrences like these are not rare, in fact they are reaching epidemic proportions throughout the performance community.
The problem stems from the failure of the needle bearings in the roller wheels to withstand the pounding of high performance valve trains. Its not a new problem, The axle and needle bearings never were capable of supporting the increased loads of high performance engines, with any reliable endurance, and this goes back to the sixties.
“BREAKTHROUGH" NOW, the Solution: After more than eighteen months of research, development and testing, Schubeck Racing, introduces the first major design change for roller lifters in nearly FIFTY YEARS.
They are called ROLLER-X Lifters and they solve this long-standing problem by eliminating the source of the trouble. This was done with a total departure from current lifter designs that use needle bearings.
The new ROLLER-X Lifter design features a roller wheel that has no center hole for an axle or needle bearings. The solid roller wheels roll as normal, against your current roller cam, but gone are the troublesome needles and axle.
This is not a new science, similarities are taking place in other areas of the engine, such as the connecting rod bearings that float on a film of oil around the crank journal. The bearings, separated by a cushion of oil, never touch the crank journal, and yet, the rod’s driving force still turns the crank. This happens through a combination of mechanical and hydraulic forces working together and all made possible by a law of physics that states, "You cannot compress a liquid”. In this case, the oil is the non-compressable liquid, trapped between the bearing and the journal, preventing them from touching.
To further illustrate: The rod bearing, contoured with the exact same shape as the journal, is forced against the journal by the power of combustion, but the two are kept separated by the non compressibility of the oil. This separation between the two surfaces continues until the supply of new oil is overtaken by the rate of oil escaping between the two surfaces we call the impact zone.
For the same reason, ROLLER-X Lifter wheels, ground with the same precision tolerances to conform to the contour of the adjoining bearing inside the lifter, share the same benefit of the oil barrier, allowing the cam's force against the spinning roller wheel to lift the valve, without the wheel ever touching the seat where it nests inside the lifter.
Needle bearings, on the other hand, because of their round shape, make only a knife edge contact with the surfaces they separate. Consequently, because entrapment of oil is not possible, they do not benefit from the same law of physics. With needle bearings, there are no flat or parallel surfaces to impact the oil. It's purely a metal on metal contact where no amount of oil, submerged or sprayed at high pressure, stands a chance to come between the knife edged contact line of the needle and the two surfaces they separate. The harmonics of the valve train hammer at the needles until they are flattened enough to escape their cage. Then its only a matter of "TIME".
The days of racers being plagued with that age old problem of having no alternative but to use needle bearing roller lifters that end up destroying their engines, are numbered!!
The new 'Drop-In' ROLLER-X Lifters, available from Schubeck Racing on a factory direct basses, for Chevy (.842), Ford (.874) and Mopar (.903), come also in combinations of centered and offset push rod seats. Coming soon are Roller-X Lifters for Harley Davidson, Volkswagen and Ford Flathead engines. Sizes up to .937" and 1.00" diameters are available.
Roller-X Lifter installations require machining a key-way slot, partway down on the inside of the lifter bores. The key-way serves as a track to guide the protruding keys attached to the lifters, preventing rotation in their bores. A key-way fixture has been prepared for each model which includes the necessary drill bit and instructions for the simple machining operation. Gone also, are the days of the troublesome and dangerous floppy links between lifters pairs.
Future sales of Roller-X Lifters using Guide Bars will be available only on applications where blocks such as Gen-6 & LS-1 came equipped with roller cams and anti-rotation lifter hardware from the auto maker.