i have a 2002 chevy 2500hd with cold air throttle body spacer and exhaust also have a diablosport predator. Should i change from the predator to nelson or blackbear tuning? Would i notice that much difference if i did?

 

yes, if you switch there's a huge difference. I went from one to a Wheatley tune cause he's in Houston and I'm right by it so it made sense. but I noticed a huge difference. went from 13 mpg to 15.5 mpg even though I still drive the same and the power is beyond what a programmer can do for you..just sell it and use that money for the tune