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Originally Posted by lust4speed
I'd say that #7 was leading the pack and failed first but would also bet that the remaining 15 lifters and lobes are all showing varying stages of failure.
Seat pressure isn't what kills flat tappet assemblies and base circles of the cam after a failure usually looks pretty normal. It's the open pressure that wears the lifter and failure point is the nose of the cam. Not all springs are created equal and you can have satisfactory seat pressure but the spring rate might result in too high of open pressure. Using stock length valves and stock installed heights really requires that the correct spring be used and not something on steroids. My target is usually around 115 pounds on the seat and 260 open for a mild flat tappet like the 068. It is easy for some strong springs with higher lobe lifts to be around 350 open and that can spell a quick failure.
Life would be easy if the lobe and lifter produced chips large enough to not go through the pump screen, but the particles form a type of slurry that passes right through the screen and pump. A good filter catches most of the crud and bearings don't usually look that bad. I've found the main hiding place for the garbage is in the ring lands and the wrist pin area of piston and rod. Proper cleanup can be really tedious.
My favorite lifter is the Crower Cam Saver hydraulic flat tappet lifter where they have added a slot down the side to increase lubrication. Lifters are made by Johnson for Crower.
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I’ve been considering the cam saver lifters over the Hylift Johnson’s but there’s no mention anywhere that the Crower lifters are made in the USA so I’m hesitant to purchase them.