I would have to dissagree with you 98Navi . I bought my tuner for improved shifting and to adjust my speedo . I am very happy with my 87 performance tune from vmp .

 

Hey Navi - You are correct. The higher the octane level the more the timing can be added. Octane slows the burn of the fuel to allow more time for the ignition.
We only have 91 here, but I'll pay the extra five bucks a tank....