Looking to get more horsepower out of my 2003 Silverado 2500HD, I have installed a Velocity Cold Air Intake, BBK Performance Headers and a MBRP Performance Cat-Back Exhaust System. Other suggestions were upgrading to 4.56 gears (not sure if I that's the best?), installing a throttle body and buying a programmer. I can get a Quadzilla Stealth 2 Power Programmer for $291, a Jet Performance Programmer for $338, a Superchips FlashPaq Tuner for $340, or a DiabloSport Predator Tuner for $340 and the PC Interface USB Cable Kit for an additional $40, so $380 altogether. All claim HP/Torque gains of 20+, better gas mileage, better throttle response, recalibrate for the bigger tires, etc. All of them have received 4 1/2 out of 5 stars or better by customers, so not sure if I should go cheap with the Quadzilla at $291 or go with the Diablo at $340-$380 because of the name/recognition, $49-$89 is a big difference for me. Any and all advice would be helpful.

 

Go Blackbear performance tune. I wish i had mine already to give a my own opinion. But in the 9 months I've known about blackbear, I've never heard a single bad thing about them. Everyone I've talked to that had a Blackbear Tune, 2-3mpg better, had more torque, faster response, and the engine ran much smoother. I'll be getting my tune soon enough. And I'll post when it's done and what I think.