Mopar Performance Lifters

I have always found Mopar performance lifters to like very little preload 0.50 or less. As mentioned earlier I have run direct connections / Mopar performance lifters almost exclusively and are currently running them in my 340. I would truly hesitate to think that it's lifter failure unless something weird happened during break-in. I will tell you that I have had those lifters clatter around for a while after a cam replacement for the first few startups and then just settle in and perlite kittens for no apparent reason. Also when I went from stock to adjustable rocker arms it took a while to get it dialed in.