Lifter failure

lifter problems probably been there all along
just in a market where most families owned 16 or 32 64 flat tappet lifters the chances of hearing about a bad one were lower
these days many families have no flat tappet lifters the audience for a new flat tappet lifter is very small, therefore if 1 in every 10000 sets was always bad, most of those got spotted before the engine was in the car or before the car sold, or in warranty. its now 1 in every 10000 old car guys who finds it, and they all know each other and express their opinion to a receptive audience of other old car guys.... no longer 1 in every 10000 of the whole population who gets it fixed under warranty and probably didn't even take note of what the problem was.

60s 70s 2 big companies in the US made all the flat tappet lifters and sold billions of them
80s/90s manufacturers start to move to roller lifters and catalytic converters dictate less ZDDP in oil so the 2 big companies are now only making millions
today 1 company sold out to delphi who shut down flat tappet production and converted production lines to roller lifters the other is hylift johnson. any others come from ??? both mexico and india are places that cost iron stuff comes from federal and melling sealed pro and well lots of companies get perfectly good stuff made there.. but its still a tiny market these days

80s/90s
Less ZDDP in oil impacts all good and less good daily use oil but not so much the aftermarket racing stuff. guys are caught out

2000 - now we don't tend to use oil from the local chevron station because its for modern cars we know about zinc additives
2000s- now the one US company making flat tappet lifters now makes 10s to 100s of thousand and the only place they are needed is the aftermarket for really old engines.

keep in mind the lifters maybe just the same it could be something different with the cam material when the vast majority of cams are now made of materials for roller lifters. did something spoil the recipe for a nice flat tappet cam blank....?

I know 1 guys who insists the problem is abrasive materials left on the cam during manufacturing, recons care and attention to detail in the manufacturing process is long gone, cheaper tooling used in grinding, why invest if you're only making a fraction of what you used to.... some substances used in grinding no longer allowed due to health and safety etc. scrubs his cam with nylon pads and WD40 before fitting, coats it in assembly lube and leaves it to marinate :) (stops flash rust) and checks for lifter rotation..... hasn't had a problem

obviously just a view and no idea why, i doubt he has any fantastic insight into the manufacturing process, he builds lots of engines though


dave