[klebel]

Am I reading this right? You install a high horsepower tune and you are unhappy because your mileage dropped? Dude sell the car and get a Prius. You don't deserve that ride.

[Surquhar]

Originally Posted by mithiral67

on 93 map and after fill up. I am happy with my mileage.

Dam - Thats awesome! I have an AP and I avg 19-21 with or without. I made a few 3 hr + trips and tried to improve my avg but no luck. Its weird that our avg's vary so much.

[Jeff@TopGearSolutions]

When I was commuting 50 miles a day I was avg 24 MPG combined regardless of tune.

Now since I drive my car more for pleasure its about 19-20 MPG tuned.

Naturally the more city driving the more that number decreases. This car has horrible gas mileage for city driving. Like 11 MPG lol.

99% of the time gas mileage varies from driver habits and conditions. Most tunes usually increases gas mileage on the highway believe it or not as they are usually tuned with better ignition. (if done right).

I wouldnt be too quick to judge its the tune, perhaps you had a scenario of more stop and go traffic, red lights, or idle time throughout your trips.

[E90Vader]

I'm back on the 91 octane map. I love it, it does get better gas mileage because it doesn't seem like the turbo's are boosting as high with light throttle response. I can also use shell v-power to fill up and I'm not stuck with finding Husky's for 94 octane.

I also feel more comfortable as it is easier on the engine since I don't have supporting mods.

The mileage difference is about 50 - 100 per tank, its not that huge but I think the biggest factor is the 93 tune bugged me for a few reasons.. I hate husky fuel, I was concerned about my engine without an FMIC or DP and it did get worse gas mileage as I couldnt give it any throttle without boosting high.


I hope stage 2 has a strong 91 octane map that still dishes out tons of power.

[E90Vader]

I'm back on the 91 octane map. I love it, it does get better gas mileage because it doesn't seem like the turbo's are boosting as high with light throttle response. I can also use shell v-power to fill up and I'm not stuck with finding Husky's for 94 octane.

I also feel more comfortable as it is easier on the engine since I don't have supporting mods.

The mileage difference is about 50 - 100 per tank, its not that huge but I think the biggest factor is the 93 tune bugged me for a few reasons.. I hate husky fuel, I was concerned about my engine without an FMIC or DP and it did get worse gas mileage as I couldnt give it any throttle without boosting high.


I hope stage 2 has a strong 91 octane map that still dishes out tons of power.

[bkrM3]

Welp, I have to say I'm pretty impressed with Cobb on gas mileage. I drove across Pennsylvania (east to west) yesterday morning, which has tons of altitude change, weather change and traffic inconsistency. Basically not an ideal situation to max out mileage. I also didnt use cruise at all and enjoyed the occasional pull up to...uhh..."fun" speed. As you can see, my overall average speed even after spending 20 minutes in town and on small roads was almost 73, so I didn't exactly crawl.

ANYWAY, onto the results:

Cobb AP stage 1 93 octane v2.02 (standard), 6MT 335i
367 miles
26.7mpg

I've done this drive more times than I really care to count and I've previously got between 27-28mpg...I seem to recall getting a hair over 28 once when I drove slowly and used cruise. The take-away (at least for my car) seems to be that Cobb 93 map horsepower has come at a fuel efficiency cost of about 1 to 1.5mpg for highway driving. With that result, it's not even worth changing maps to try to achieve better efficiency.

That said, it was about 60 and rainy yesterday and I have no idea how fuel efficiency will change if I do this trip during the normal, super-humid 90 degree Pennsylvania summer. With higher IATs (and, therefore, higher boost as a result of load targeting), it'll be interesting to see how this changes.

Btw check out my oil temp. It was 1-2 ticks below 250 for the whole drive. My car has the OEM aux. oil cooler.

[E90Vader]

Your so lucky! Its got to be the fuel you are using.
If I use Husky, its shit and the car gets horrible mileage.

Had to go back to 91 octane, and on this tune the gas mileage is incredible!!!!!

[redwinger]

not to hijack this thread, but I find that hwy mileage depends drasticly on your speed. At 70mph I get around 30mpg. At 80 I see around 23-24mpg.

[Jeff@TopGearSolutions]

Low speed boost swings and heavy throttle gear changes will result in poor gas mileage.

Its best to control your right foot as much as possible and stay out of boost if your not looking for power.

Low Boost fuel columns usually need about 2x more fuel compared to their 0 Vac counter parts. (Easier said just 2-4 PSI can waste 2x more fuel then if you stayed out of boost).

[E90Vader]

Until we get a more reliable 93 octane fuel source I think I'll stay with my 91 map.
I just ordered AR Catless DP! When I have then installed I'm also deleting the secondary cat, as well as deleting the muffler! I'll have completely straight pipes from the turbo back.

Will this make a difference with the 93 tune and higher boost? Could I run it safer then without any suporting mods aside from the AFE DCI?

[zeenon53]

A little OT but it's funny how the OP talks in MPG and compares it to speed in Km/h.

[E90Vader]

I live in Canada, I don't understand MPH very much, only KM, but I never did learn or understand K / per litre or whatever that conversion is... I only know MPG as for as driving goes.

At the end of the day I realize I wasnt so much worried about gas mileage, rather I was concerned about how hard 93 octane tune was on my car without supporting mods. Hoping it will be easier with straight pipes, otherwise I'll still keep it at 91 octane.

[E90Vader]

Was cruising around today with 93 map. Honestly, its easy to stay out of boost.. I think it was all in my head.

However, I get this funny feeling where I just want to push the pedal down!! It's like the red button that someone tells you NEVER TO TOUCH!. I'm sticking with 93.

[Bcruskie]

Im on JB4, at 14psi I get 30 mpg on the hwy.
I find the 90km/h (55mls/h) banks at 35mlg.
My personal sweet spot is at 105km/h (65mls/h), auto box sits at 2000rpm in sixth gear
windows always closed. I also use Chevron 94, it does not contain Ethanol and I statistically prooved to myself gains in mpg.

in just city drive, I get 20mpg consistant milage. Used to commute 50 miles (15 city/ 35 hwy) with consistant 26 mpgs across.