[JLMounce]

Fwiw I’ve had Lunati link bar lifters on my comp hr for about 15000 miles. I’ve not had any performance or reliability issues with them. They clatter terribly when the engine is warm however. Clearly collapsing.

It’s not just the lifters that are a concern here. The oiling system in basic street builds seems to be an issue as well.

I’ve followed everyone of of these threads and from pulling ideas, thoughts and observations from them all, not only do we need a quality lifter with good internal tolerances and QC, but the engine also needs to be able to supply (by my estimate) 30psi of oil pressure at hot idle.

If like me you have an engine that will only hold 15 psi on a 10/40 oil at 900 rpm hot, and you match the system with a set of lifters that have looser internal tolerances. Well, that’s a recipe for a noisy valve train.

While I haven’t had any reliability issues with my lifters, the constant hammering of the lifter internals at idle as the lifters collapse can’t be good for them.

Given my experience and research I believe that a modernized, well built and blueprinted oil pump, setup to supply 30-40psi at 800 rpm is a requirement to a successful hydraulic roller cam conversion. Along with choosing good quality lifters that have a correct oil band height. Whether those lifters are link bar or using a dog bone as it’s capturing device.

There are obvious cost and weight advantages to this setup being discussed that makes it so intriguing.

[Sirrotica]

Originally Posted by JLMounce

Fwiw I’ve had Lunati link bar lifters on my comp hr for about 15000 miles. I’ve not had any performance or reliability issues with them. They clatter terribly when the engine is warm however. Clearly collapsing.

It’s not just the lifters that are a concern here. The oiling system in basic street builds seems to be an issue as well.

I’ve followed everyone of of these threads and from pulling ideas, thoughts and observations from them all, not only do we need a quality lifter with good internal tolerances and QC, but the engine also needs to be able to supply (by my estimate) 30psi of oil pressure at hot idle.

If like me you have an engine that will only hold 15 psi on a 10/40 oil at 900 rpm hot, and you match the system with a set of lifters that have looser internal tolerances. Well, that’s a recipe for a noisy valve train.

While I haven’t had any reliability issues with my lifters, the constant hammering of the lifter internals at idle as the lifters collapse can’t be good for them.

Given my experience and research I believe that a modernized, well built and blueprinted oil pump, setup to supply 30-40psi at 800 rpm is a requirement to a successful hydraulic roller cam conversion. Along with choosing good quality lifters that have a correct oil band height. Whether those lifters are link bar or using a dog bone as it’s capturing device.

There are obvious cost and weight advantages to this setup being discussed that makes it so intriguing.

Just to add to this on ticking hydraulic rollers problem, Tom S had mentioned on one of these threads, that one of the manufacturers had said the fine dirt in the oil is also a culprit, and it was essential to keep very clean oil in the engines. Having worked on hydraulically operated machines as part of my job, the spec for most of the hydraulic filters is 10 microns because of exactly how these lifters are built internally, and tight tolerances, the same as most hydraulic valves and spools in any hydraulic system will stick with virtually any contamination.

Just a suggestion that some of the inferences are that the oil filters may not be fine enough to keep fine materials out of the oil, and cause ticking lifters. 10 microns is not attainable with a conventional oil filter. I'll just leave it there, so I don't stir up the anti by pass oil filter groups. It may or may not be a factor, just throwing it out there that fine particulate could also be a factor that is causing some of the ticking problems.

I have roller lifters in both my LS2, and my 6.5 diesel equipped with by pass oil filters, and have never had any ticking with 140,000 miles on the LS2 or 270,000 miles on the 6.5 diesel. My 3.1 V6 in my 118,000 mile 99 GP does not have a by pass filter, and I do occasionally have lifter ticking with it. It will get a by pass filter as soon as the weather warms up a little bit.