This has been asked before, I know, but I didn't find any definitive answers. I hopefully am gonna be ordering a Gryphone by the end of the week along with custom tunes.

Now the question: Has anyone done any real testing/comparisons between using 87 and 91 tunes? What I'm referring to is the difference in performance/mileage between the 2 octane levels. Is there big enough difference between the two to justify spending 20-25 cents per gallon more for Premium gas?

I ask this because I don't want to be switching back and forth between octane levels. My intentions are to order custom tunes, tow and perf, both in either 87 or 91. The station where I buy most of my gas has 93 instead of 91 so I'm covered there. I'll always have a 87 tune available in case I get in a pinch.

Before anyone gets on the stump, I'm not buying this to create a gas-mizer. I'm buying it to enhance the performance of my truck, period. If there are mileage gains they are certainly welcome. As long as mileage doesn't suffer, I'm fine with it. My biggest enemy is my right foot, I'm fully aware of that.

Thanks for your help guys,

David Walker

 

David, everyone seems to agree that using high-octane gas with a tune designed for it increases the power and torque available. How much? I seem to remember some dyno runs somewhere a long time ago that showed an increase, but I don't recall exact differences, only that it was noticeable.

If gas price is no object and high power makes you happy, I say go for it. In my case, I feel the truck has enough power with 87 octane gas and a custom tune (but I'm a grandfather).

- Jack

 

I tow a 5k lb boat and I elected to stick with custom 87 performance and 87 tow tunes. I'll keep the canned 93 performance (will never use it).

IIRC a couple of owners did the experiment and the math several months (or is it years?) ago. One determined the MPG gain paid for the 93; another determined it didn't. Just proves (to me), it depends on the driver, the truck, the moon position, etc. In other words, no promises.

You could always order a custom 87 performance, custom 93 performance, and leave the stock 87 tow. Try out the performance tunes. If you like the 93, change the tow tune to a 93 custom.

 

Thanks guys. I haven't done the math yet to see how much mileage difference there would have to be to pay the upcharge. I suspect it's gonna be the same as my usual SOTP assessments; It makes a little difference, but hardly noticable. I'll probably just go with 87 tunes and be done with it. 1000 gallons from now the price difference will pay for a set of airbags.

David

 

the higher octane allows more timing which our trucks need to make more low end torque to get it moving easier

when I was n/a my F-150 got 60-70 miles more per tank with the 93 octane tune

 

60-70 miles sounds like another 2 MPG. That would make it worthwhile. EX:

15mpg = 20gal at 300 miles (87/$2.50/gal x 20 = $50)

17mpg = 17.65gal at 300 miles (93/$2.75/gal x 17.65 = $48.54 )

Now if there were only a linear equation to say every truck will have those results! Unfortunately they all will respond differently.

Of course, here again, I'm not doing this for mpg's, but that'd be a definite bonus. Right now I'm getting 11-12 in town and 14-15 interstate. Not terrible considering 34" tires, but could be better.

Decisions, decisions!!!

Oh, assuming no disasters, I will be ordering this week. Finally getting paid by one of my customers so I got a little extra cash on hand. Man I can't wait, if only for tranny tunes!

Thanks,

David