VersaTune User Forum

I have a stock 2014 Miata which I'm about to install a cold air intake. I would like to save the current stock ECU tune so I can revert back to stock at a later date. If I change the intake, then drive it a while before reflashing, will the stock tune be altered by the new intake that would affect it if I reverted everything back to stock? Or would it simply relearn the A/F ratio and adjust accordingly? Hope that makes sense.

No tune will be altered by any modification you make to the car. However, the ECU logic has various ways for adapting to such changes, as well as to ambient changes (altitude/barometric pressure, temperature, humidity, and so on). The ECU will keep track of these deviations in tables stored in the volatile memory, so every time you disconnect the battery or reflash the tune these vectors will be reinitialized. The tune itself is stored in the permanent memory of the ECU and that cannot be altered unless you are using dedicated tools (such as the mazda factory tools, or versatuner + cable adapter).
So basically installing an intake on your car looks from the ECU perspective as a big and sudden weather change (like starting your car in the winter after not being started since mid autumn when you still has summer-like weather). Calibrating the MAF properly and flashing a tune for that intake will shorten the "learning" process significantly so the car will behave smoothly from the very beginning. If the intake is significantly larger than stock you definitely need to flash a tune with a proper MAF calibration for it, the ECU still stop learning these deviations (compute the long-therm fuel trims - LTFTs, with weighted averages of the short therm fuel trims - STFTs) when they are above 20% (- or +) and will not compensate (using the STFTs) for deviations above 25%.
So depending what your case is - now you know where you are and what to do.

Thanks! I appreciate the detailed reply!!