wingman75

The safe way is to burn up 2 tanks of 93 before switching to 93 tune. But if your rich... so what... right?

speedstang06

Good question, I was actually thinking about this the other day.

06tyrfryr

it wont hurt it it to just run the car down lower on fuel and add the 93 octane fuel and go ahead with the tune, I just wouldnt go wot. I had a 93 octane tune in mine and still was able to add a few more degrees timing in it and I only have 91 octane available. but 87 is a no no with a 93 tune for sure, my wife accidentally put it in her car and nothing was hurt but it ran poorly with very little power computer was able to retard the timing to keep it from damaging the engine

jz

I did similar to most everyone else here. Ran a tank of 93 on my stock tune. Filled up again, ran that about 1/2 way down then filled up again with 93 and finally installed my tune. Didn't have any problems, but also carefully listened to the engine under wot. Good luck, you'll love the 93 tune and wonder why you didn't do it sooner.

Joe