The root cause is the rocker shaft not in the optimum location from the factory. There's a lot of good info on Mike's site. It's worth a read. If the rocker shafts were optimally located by Chrysler, none of that would be necessary. Mike has one simple measurement you can take that will show you that basically none of the stock engines has the rocker shafts in the right place. I've measured several big block, small block and slant 6 heads and they are all out of spec for what is considered optimal. Mopar guys have dealt with rocker to spring interference for decades. Mike just figured out why and offers a correct fix.
