Ok to make the truck shut off and not deisel it has to be at like 20deg. before, but then it doesnt run right and pings when i get on it. If I get it at like 8 before it deisels when I shut it off but runs good when on it...question is what does advancing the cam or retarding the cam 4 degrees do? and if you have any other suggestions. It's a 350 .30 over 400 crank, erson cam 9 to 1 compression i think i need to check it. Thanx Chris MY DRINKING TEAM HAS A FOUR WHEELING PROBLEM!