think it will float the valves at 5k with stock valve train? does the mopar magnum performance springs allow for more lift or it the lift limited by the valve guide height? I dont want to pull the heads. I can fab a spring compressor and air up the cylinders to swap the springs, they only cost about a 100 bucks too. If its gonna make a huge difference in the engine for less then 400 bucks with a regrind and springs then it maybe worth it to me.