my "normal" 1/4 mile ET is 15.32-15.40, with a trap speed of 88-89 mph.....not the fastest but certainly no slouch for a 5600 lb truck with very few mods..

I was out today playing around with my G-Tech.....I was out on the same stretch of road (an old abandoned airstrip near here with a good launch area and plenty of runout at the end) I always use to test on and the weather was about the same as normal....the ABSOLUTE best that I could achieve today was a 16.8@78 mph ...what the HELL happened...I have changed NOTHING from my normal setup (intake/exhaust/TB bypass)

My truck felt like it had NO bottom end at all, it normally will spin all four tires in 4X4 about a half rotation upon launch...not today !!, the stock converter normally stalls to 1700-1800 rpm's...today it wouldn't stall higher than 1300-1400 ??......WHAT THE HELL GIVES HERE

HELP !!

 

May have been a little warm?
Was that power sucking mechanical fan robbing all the power from the engine? What about the AC, was it on?