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Discussion Starter · #1 ·
Hey guys I switched to 93 fuel and changed my tune to 93-Race from Bama. It now seems that the car is a little quicker. Is it common for me to see an increase in fuel mileage.
 

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US Air Force (retired)
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Probably not. An increase in power is usually a result of using more fuel not less. And that is if you drive the car exactly the same way as before. If you enjoy the peppy feeling and start driving more aggressively then you will definitely see a decrease in fuel mileage.

The car manufacturers have to meet the fleet fuel mileage goals set by the federal government. If a tweak in the tune would have given more horsepower and greater gas mileage then they would have made that a factory setting. Ford actually changed the oil grade recommendation from 5w30 to 5w20 in 2001 to get just a tad more mileage because they were facing government fines.
 

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King Trashmouth
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I'm going to go out on a limb here and disagree with Eagle for once.

I'm going to guess that the primary difference in that tune is they just increased the timing (mostly as allowed by the increase in octane.) That alone will net you more peak power as well as more power with the same fuel. That means when you're cruising around needing a certain amount of power, you actually have to put less fuel in than before, because now you can make the same power with less fuel and more timing.

You can really see this in diesels with aftermarket tunes. Turn up the timing and your fuel economy goes waaaaay up.

The reason Ford didn't do this from the factory is 98% of their customer base isn't going to pay for 93 fuel, so it's tuned for 87. In addition they have to keep warranty low, so they're going to be very conservative on timing in the first place.
 

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It depends on the vehicle and the tune. A lot of newer cars are actually tuned to run consistantly rich from the factory, and if you adjust the tune and get the fuel curve a bit closer to stoich in some places, you can actually get more power with better fuel mileage. This was the case with my SHO. When I went from the base tune with 93 octane, to my final 93 octane tune, with 15psi commanded boost (stock is usually 10-12 but isnt a set max boost).

My gas mileage didnt really change in this case, but I increased power and kept the same gas mileage. In a N/A car, this could be done with an increase.

That said Eagle is also right. Though some cars are left at lower numbers because they know people will modify, etc.

I am skeptical of this scenario with your BAMA tune though. The BAMA tunes are almost ALWAYS pig rich. Mine had close to 13.5 AFR at IDLE on my 6 on their first revision. That is stupid rich for idle.
 
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Another thing to remember is that the 01-04 cars came with 21# injectors and run rich from the factory because the ecu isnt calibrated for them. If Bama knows this then I could see a tune adding power and better fuel economy.
 

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Another thing to remember is that the 01-04 cars came with 21# injectors and run rich from the factory because the ecu isnt calibrated for them. If Bama knows this then I could see a tune adding power and better fuel economy.
I remember a discussion with CliffyK. He said Ford added the 21 lb injectors without changing the 19 lb injector tune. (I had forgotten about this. My car came with the 19s.) I think his exact words were that the cars ran "pig rich."
 

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Another thing to remember is that the 01-04 cars came with 21# injectors and run rich from the factory because the ecu isnt calibrated for them. If Bama knows this then I could see a tune adding power and better fuel economy.
I remember a discussion with CliffyK. He said Ford added the 21 lb injectors without changing the 19 lb injector tune. (I had forgotten about this. My car came with the 19s.) I think his exact words were that the cars ran "pig rich."
Thats exactly where that came from. As long as Bama knows this the op should see both an increase in power and fuel economy but who knows.
 

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Discussion Starter · #8 ·
ahh ok it makes a little more since now. I was driving it like i stole it and it stayed on F for the first 35 miles
 

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6 Cylinduh, Really Bruh?
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ahh ok it makes a little more since now. I was driving it like i stole it and it stayed on F for the first 35 miles
Hell yeah!!

Sorry had to say it.

I didn't notice a bump in mpg but I drive the car pedal to the metal when I drive it. These higher gas prices are killing me on 93 octane
 

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Discussion Starter · #10 ·
I want to do gears 3.73's and I'm trying to find a CAM that i can use later with my 2.1 KB blower that i'm pre planning my xmas bonus for lol
 

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Discussion Starter · #11 ·
Hell yeah!!

Sorry had to say it.

I didn't notice a bump in mpg but I drive the car pedal to the metal when I drive it. These higher gas prices are killing me on 93 octane
they have 93 no ethanol i might give it a go. I heard you can feel the difference. Will i have to get another tune?
 
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