yukmouth

hey guys, my buddy has a gt and after riding in mine he chose to get a cai/tune from brenspeed he recieved it today in ups, but he has a 1/4 tank of 87 gas and wants the 93 tune. should he just wait till its low fuel and fill it up? or is it okay to fill it now with 93 and load the tune?

s197richie

^^^ I'd take a road trip, get it good and empty and then fill it up with 93, then load the tune,just to be safe. From what I've heard, running a lower octane than the tune requires can cause engine damage...better safe than sorry...besides, what's a quarter tank in a mustang, 50 miles maybe? lol...

hammeron

i would install the cai and load an 87 tune.
run the 87 tune until you're sure there's no
87 octane fuel left in the tank....

yukmouth

hmm would 0 miles to empty be good enough to assume theres hardly any left in the tank?

howarmat

yes

yukmouth

ok great! guess were taking a road trip then

unsocbl

I actually ran through 2 complete tanks of 93 before switching tunes. Read too many posts about knocking and pinging with the higer octane tunes.

yukmouth

maybe after he fills up he can just put that techron stuff in? would that help the tank burn fuel more efficiently?

s197richie

at zero miles you have one gallon left...just fyi...

StangPilot

how about some octane boost? mine ran fine that way.