My truck with gde tune did 245 wrhp with water methanol shut off, with water methanol turned on did 260 wrhp. With my ppei tune it does 272 wrhp with water methanol off and 287 wrhp with water methanol on. Very impressive numbers for a somewhat stockish truck. All this talk about extra power overstressing the engine is unfortunately not very true yes egts can get excessive but thats easy to moniter. The bottom end failures have nothing to due with power there from machining errors, assembly errors, and design flaws. Just a fyi my ppei and gde tune get within .5 mpg on average.