I've been running 87 for 3 years. I know have a superchip programmer and wanna run the 93 octane setting..do I need to run thru a full tank or 2 of 93 before i use the tuner?or just fill up, tune and go?

 

I don't have the Superchips, I have a Bully Dog on my 2012, but I ran the tank of 85(85 is regular at this altitude) down till the low fuel light was on and the display said "low Fuel" where it normally gives miles to empty, filled it up with 91 and set it for the premium tune.....worked just fine, if your worried I guess you could throw in a bottle of octane boost from an auto parts store.....

 

This won't answer your question but I was running 93 and went back to stock before getting the fuel tank recall completed at the dealer. When I reprogrammed it, I decided to try 87 and can't feel a performance difference between the two....just easier on my fuel cost

 

I would run the old gas as low as possible, fill it with 93, and run the tune.

 

I find that my 2010 jk doesn't like the 93 octane tune I found that it runs best with the 89 octane tune and 94 octane fuel, the 93 octane tune is to much for 94 octane fuel, I'm sure it would work good with octane boost and 94 octane fuel

 

just so you all know. ethanol raises effective octane of gas. they use the same 85-87 octane for regular and add 10% ethanol, typically raising effective octane to 90-92 depending on the water content of the ethanol before added. some companies use slightly more ethanol than 10% son we will be used to 15% which will be the typing point for pre-98 vehicles having problems with fuel line deterioration, well faster.

 

Been running 93 for almost 2 years and love the tune.