Reply to "Hydraulic roller lifter issue?"

Doug, I tend to agree with you. Hydraulic roller lifters should be reliable. After all, they are OEM in 5.0L Mustangs where they do not have reliability issues, that I’m aware of. The problem is, the lifters are heavy, which creates the need for heavy valve springs to control the inertia they create. Solid roller lifters are better in this regard. These heavy springs create a very hard, short life for the tiny needle bearings that live inside the rollers. The only partial solution is to lower your max RPM expectations and fit the very lightest valve springs possible. That’s how Ford dealt with this issue in the 5.0L. Solid roller lifters are a bit lighter than hydraulic roller lifters, so they can get away with lighter valve springs. As a result, they are more reliable
As I mentioned in Marlin’s pilot bearing thread, Isky makes solid roller lifters that use the same style of bearing as his pilot bearings. No needle bearings! Unfortunately, they are expensive and so far unavailable as hydraulic lifters.