zero lash

  1. cjstang6791

    Engine '67 Mustang 289 V8 Loose Rocker Arm Polylock Nuts Wtf?

    Trying to tune and road test my '67 Mustang 289 V8, but for some reason, the POLYLOCKS KEEP COMING LOOSE, and not always on the same cylinder or bank -- sometimes left, other times, right. I'm confident the valve adjustment procedure and pre-load and zero lash have been done correctly (performed...