Mach 1 Changing Predator tune?

I recently bought an 03 mach/auto with some mods. The previous owner installed 4:10's, bassani offrd x/c back, ported manifold, c&l intake and mass air and suspension. He had the car tuned a year ago (professionally) and had 3:55 gears at the time, but never had it retuned for the 410's. Now the speedo is about 8-10mph off and I want to correct it with the supplied predator that was initially used by the installer. Can I go into the tire height setting and make the change without screwing up the tune or do i have to take it back to the shop where he had it done? Thx

Give Me TP said:

You can change it yourself. 4.10 ratio, as well as other ratios, is adjustable by you under the "axle" menu.

Click to expand...

Thx, but when changing the ratio's will the current tune be wiped out? I guess what Im asking is, when I pug in the tuner will it take out the current tune and cuase me to take it back to the installer to retune, or will all current tunes be saved and once I correct the speedo just put the current tune back in. I want to adjust the ratio mself, but afraid of screwing up the tune thats in the car now.

Give Me TP said:

You may be able to go in and change it now, but if not re-load the original backup (the copy of the factory tune stored on the predator), and then re-load the custom performance tune back on. The predator should give you the option of modifying parameters, including gear ratio, at the beginning of the download process for the custom tune. Either way, the current custom tune will not be lost or screwed up by doing so, because I have done that same ratio adjustment myself with my Predator while a custom tune was loaded on it.

Click to expand...

Thx man, big time.