Daveo2k6

Hey guys so i got a tuner from AM.com and i got a 93 octane tune. I called Bama about how to switch gas and what he said was run my 87 gas as low as i feel comfortable then fill about a quarter tank with 93. Then afteri run that quarter tank down fill up with 93 octane. Only thing he forgot to tell me was when to tune? haha I was gonna call them back tomorrow but figured id post this and see what i got

thanks guys

ct_white_stang

After the second fill up. You could also just add a can of octane boost too just to be sure. I would just run down your tank of 87 fill will 93 and then tune. The octane boost will just give you safety though.

sonicx

Thats a good question, i was going to ask myself actually lol. (Not trying to threadjack) So then if you wanna switch back you do kinda the same thing?? Would it hurt your engine to be on a 93 tune w/ both 87 & 92? Sry, I don't have 93 where i live???

5pointslow91

id say after you run the 1/4 tank of 87 and then the 1/4 tank of 93, then fill it up with 93 and once your at 3/4 of a tank then tune

FlamingoGT

You throw the chip on after the full fill of 93.
The way Bama told you has a dumbed-down aspect to it. But then they have to deal with the lowest common denominator too. I would take the tank down to under an 1/8th, fill up with 93 and add a bottle of octane boost and slap the chip in then.
Actually personally, I would do the programming myself and have it switchable for a couple of different scenerios. But that was when I had my 3rd-gen F-bodies... but I'm sure it can be done with these Mustangs too.

0949er

if you want to go reverse don't worry so much as to what fuels in the car. Running 93 octane on a 87 tune will do 0 damage to the motor. Just throw the 87 tune on and whenever the tank gets low fill it up w/ 87.

DreamerGT

Octane booster? If your running 87 and add that boost crap you will have 87.4 octane in your car. Run your car all the way low then fill up with 93 octane, then put the tune on when the needle is 1/2 down.

Cusp

Like they said. Run the 87 out, Fill up with 93, run that down real low. Fill up again, drive home and tune. BTW, when my fuel lamp comes on, I have about 3 gallons left. I only am able to get 91. But when I did it, I just ran down my 87 until the lamp came on. Filled up with 91, drove it a couple miles, installed the FRPP 91 tune from the pro-cal tool. Not any ping at all. Drove that tune for about 10 tanks of 91 before putting in a Tillman All out. No issues. The 10 tanks were not a method, just how it worked out.

Daveo2k6

Alright thanks guys for the input! I also called Bama again just so I can collectively make a decision ha. This is what I have come to..

Run down the tank of 87 octane gas as low as you feel comfortable with
Fill the tank with a quarter to half a tank of 93 octane gas
Run the mixed-ish tank of gas as low as you feel comfortable again
Then fill up completely with 93 octane gas again
Drive on this tank until you think you have run all of the 87 octane out then TUNE!

**it doesn’t hurt the engine running 93 octane on a 87 tune, BUT it is not good to run 87 octane with a 93 octane tune!

I hope this post helps other people out.. I searched the forums for a post like this and couldn’t find it!