competition cams hydraulic lifters pump up problems

[don duick]

anyone have pump up problems with comp cam lifters? I installed new comp cam with new lifters had about .020 preload. after reving the engine over 4000 it idled rough and would not run. am convinced the valves were not seating. I would let the engine sit for a while then it would run fine again until I reved it again. Took out one of the lifters and tried to push the piston down by hand and it was rock hard. I had to compress the piston in a vice. once compressed and oil was out  it was then easy to push down by hand. These are the standard cheap lifters. I gave up on preload and installed a set of crane adjustable pushrods with zero preload. surprisingly I have no lifter noise and runs fine now. I also installed them a bit loose just to hear lifter noise just to make sure they are set to zero preload.

[justcruisin]

Yep, engine wouldn't idle below 1800 rpm after a good rev, it would slowly get better over a minute or two until it would idle. I suspected tight guides on my new eddy heads but they were OK. Swapped out the lifters for some Hylift Johnsons and that sorted it. Also found casting imperfections in the comp lifters.

[don duick]

good to hear

[Challenger340]

Who knows WHAT, or WHOSE Lifters CompCams are re-boxing into their CompCams Boxes these days ?
I've had great luck using the Hylifts thus far.... but who knows in future ?
The simple fact remains, that nobody wants to continue making Flat Tappet Lifters, an obsolete design, for obsolete Engines anymore ?