CLASS RACER FORUM - View Single Post - Comp Elite Race Series Lifter Axles walking out?

nhramnl · 06-02-2016, 05:12 PM

According to a lifter manufacturer that has a reputation of solid gold, here are the things that can kill a roller lifter:

Inadequate valve spring pressure. Spring simply can't stay in contact with the camshaft and is "tossed". When it lands, the roller wheels that are facing the lobe at that nanosecond get flat-spotted and the irreversible cycle of death has begun.

Also though, too crazy a lobe can cause lifter failure because if the opening ramp is simply too severe, no lifter, regardless of spring pressure, can follow it. In this scenario as well, the valve "toss" occurs and you're headed for trouble. It is for this reason that lobe "extremism" stopped (some years ago) and rocker ratio experimentation began.

Also, this lifter manufacturer said that if neither of the above issues kill your lifters, you should still worry about lifter diameter. Since that advice, I have always opted for at least .904 diameter lifters and have recently stopped using bearings (though I admit that I don't know conclusively that bushings are more durable).

Finally, if you add a bypass fuel pressure regulator to your car, you are almost assured of never having a failure of any kind again, in addition to picking up at least two tenths and four miles per hour.

06-02-2016, 05:12 PM	#9
nhramnl Senior Member Join Date: Feb 2010 Posts: 507 Likes: 8 Liked 358 Times in 83 Posts	Re: Comp Elite Race Series Lifter Axles walking out? According to a lifter manufacturer that has a reputation of solid gold, here are the things that can kill a roller lifter: Inadequate valve spring pressure. Spring simply can't stay in contact with the camshaft and is "tossed". When it lands, the roller wheels that are facing the lobe at that nanosecond get flat-spotted and the irreversible cycle of death has begun. Also though, too crazy a lobe can cause lifter failure because if the opening ramp is simply too severe, no lifter, regardless of spring pressure, can follow it. In this scenario as well, the valve "toss" occurs and you're headed for trouble. It is for this reason that lobe "extremism" stopped (some years ago) and rocker ratio experimentation began. Also, this lifter manufacturer said that if neither of the above issues kill your lifters, you should still worry about lifter diameter. Since that advice, I have always opted for at least .904 diameter lifters and have recently stopped using bearings (though I admit that I don't know conclusively that bushings are more durable). Finally, if you add a bypass fuel pressure regulator to your car, you are almost assured of never having a failure of any kind again, in addition to picking up at least two tenths and four miles per hour.