thanks for all the help guys. i fould the build sheet on this engine and the heads were reworked with new springs, locks and retainers. new guides hard seats and all is well. the 428 has less than 1000 miles on it since it was rebuilt in 91 by then kuntz and kraft. new everything balanced and blueprinted .030 over. the only thing they didn't replace were the lifers. i replaced all the lifers and the one that caused the damage is seized up. i hope this will be the end of that problem. the motor is very tight with 10.5:1 and extremely strong. well over the advertised 335 hp for a 428cj.