Once in a while I will use high octane fuel in my stock 2000 5.4 4x4 supercab especially when I am in the States(cheaper). Is this a waste of money? Is there any benefit to using it with out a chip? Mike T states that mileage will not increase significantly with a chip but I have seen on some posts that it will. Anyone out there seen better milage with the chip?

 

I have the 00 5.4 screw with a chip and af1 fipk. I did see my mileage increase even with my foot in it a few times. I think getting a chip is the best all around mod for what it does. Just my .02.

 

Hi Peterr,

You may have perhaps misunderstood what you've seen me write about getting better mileage from the Superchip, or, maybe I just goofed in a post somewhere perhaps!

There is indeed the *potential* for getting an improvement in mpg from the Superchip. It's just not something we can absolutely guarantee as too many factors are beyond our control; how the vehicle is operated & maintained, the quality of fuel being burned, etc. This potential for better mileage with the Superchip comes primarily from the increased spark advance used on part-throttle as part of our performance tuning for premium gasoline, and is merely a by-product rather than something that happens by deliberate design. It's just a natural byproduct of this tuning, the engine is running a bit more efficiently with the Superchip, so there is the potential for improvements in mpg. We consider it icing on the cake rather than a main reason to purchase a Superchip, as it's a performance product first and foremost.

You're absolutely right, there have been *many* people right here who have posted solid mpg gains from the Superchip on these boards on an ongoing basis over the years, and there have also been some who have not seen an increase, for any number of reasons. I will go so far as to say that **all else being equal,** you should see at least a small improvement in mileage from the Superchip (not one of our vehicles here at Performance has failed to show solid mpg gains from the Superchip over the years). However, sometimes "all else is not equal," and there's the rub. If you use a premium gas that has a lower energy content than the 87 octane being used previously, you won't see a gain, and you could actually see a drop in mpg. One of many reasons why it's important to alway use the best quality fuels available, no matter what type of vehicle or whether it is modified or stock.

Usually it's highway mileage that shows the most potential for improvement, city mileage doesn't usually go up much. Highway mpg gains average about 1.5 mpg, with a few people having reported as much as 3.5 more mpg on the extreme and abnormally large end, so to speak.

To answer your other questions, using anything more than 87 octane on the stock factory program is generally a waste of money, as the engine is not tuned for it, it's tuned specifically for 87 octane and thus cannot take proper advantage of higher octane fuels. There are some of the later models that have the abilty to pick up about 2% more power when using premium gas and under heavy load, but in practical terms, it's just not worth using premium gas on the factory program. We recommend sticking with 87 octane unless you're running the Superchip.

I hope that explains it a bit better for you, & if you'd like to go over this in more detail, give us a call & we'll be happy to.

 

On my '95 I do see a mileage improvement with premium fuel, without a chip. If I crank the distributor and advance the timing, slightly more. The difference is not even close to paying for the difference in price using the premium.

From what I've seen, I might get 2-3% better mileage with timing advanced and premium. With a chip the entire timing curve is changed so the potential for mileage increase is greater.