I have had a Superchips tune in my Nissan Frontier for over two years. I run it only on 87 octane tune, Thottle restriction off, speed limiter off, rev limiter on, no advance. The truck clearly runs better, and faster throughout the entire speed range, however the biggest advance for me was the removal of the throttle restriction ..
In no way however does this tuner mess with the shift points of the transmission, as this is controlled by the Body Contol Modual, not the ECM. The cortex only flashes the ECM.
Do i save gas? No.
Why? Because the darn truck is so much fun to drive i like to mash the pedal now and then to the suprise to some very upset F150/Silverado poser truck owners ...
Anywhoo ... claims of gas savings with these devices are at best wishfull. Claims of increased fun and enjoyment are substantial.
2008 Nissan Frontier 4x4
2011 Rockwood A122