MPG on new ST

[PostDigger]

I was on highway for an hour saturday. Using octane booster my mileage was 42.4 mpg.
I thought that was amazing.
Anyone else have great mileage like this?

 

[me32]

Never had that high avg. Best was 37mpg on ca 91octane

 

[sikedsyko]

If I cruise around 65 my car is in the 38mpg range. Problem is, 65 is doable on Texas roads and fuel economy drops off quickly above 70.

 

[RAAMaudio]

FYI, Octane booster allows more timing advance or more boost with less chance of detonation but it does not add to fuel mileage, at least none I have ever heard of. Higher octane fuel has less hydrocarbons than regular fuel thus it takes more fuel to make the same power.

If there have been changes since the last time I needed to deal with Octane increases beyond pump fuel it was to run race fuel or Meth/Water injection to make the power I wanted safely, I have not heard of them.

Of course I am open to learn new things, always, anybody have more info on this?

 

[iso100]

I just run 93.

I got ~33MPG coming back to MD from VA via Skyline Drive. In normal suburban driving which is both "city" and some shorter highway segments I average 27 mostly.

 

[PostDigger]

I mentioned the octane booster only because I had put some in at fill up.
I didn't mean to sound like it was getting the credit girl the great mileage that I am getting.
I drive 25 miles to work and so far have averaged 31-33 mpg depending on the weight of my foot.
Is this because my car is only a week old?
I have put about three tanks thru it in the short time.

 

[rodmoe]

I mentioned the octane booster only because I had put some in at fill up.
I didn't mean to sound like it was getting the credit girl the great mileage that I am getting.
I drive 25 miles to work and so far have averaged 31-33 mpg depending on the weight of my foot.
Is this because my car is only a week old?
I have put about three tanks thru it in the short time.

I did read somewhere about a fuel additive that GRM tested and it did help get better MPG as well as other things and it was SCCA approved ..

http://grassrootsmotorsports.com/articles/lightning-bottle/

 

[RAAMaudio]

That is cool, I will check it out.

As for the octane booster I just like to post what I have learned right away as sometimes those new to cars, tuning, etc....do not understand such things and then go off and waste money on something they do not need. Just looking out for them

 

[NorthernProducer]

I've never gotten close to your MPG, PostDigger. I usually see between 27 and 30 mpg, but then I have a hard time keeping my right foot under "control" on occasion. BTW...I only run 93 octane (no alcohol) in mine.

 

[PostDigger]

I am trying to keep my foot out of this new tank of fuel. We will see how my average is then.

 

[RAAMaudio]

The way I like to look at this is great mileage when needed, just cruise and take it easy.

Time to play, does not count, usually.

I built a very fast, highly modified, $30k in mods, Forester XT, it still got 28MPH on the road and playing around a bit...on track, double priced race fuel, 8MPG, ouch! AWD, JDM diffs, JDM or better all other parts and mostly better, 285 slicks, full interior, tuned for fuel mileage over power, modest turbo upgrade so only 275WHP and 280ft lbs, measured at 5,000 elevation on AWD dyno so some losses, 4:44 gears, fast enough I passed a full race STI and the head instructor at MMP came down from the tower to check it out, when he saw the car looked stock, etc, he was blown away by my lap times.

I would drive to the track with as low fuel as possible, half tank of race fuel added, run a session, add a few gallons, run another one, add a few gallons, etc....140mile round trip, 80 minutes on track, $275 for fuel.......for the day, more than most of the track fees.

I am very curious what my ST with an upgraded stock turbo, all the bolt ons, highly dialed in suspension, BBKS front and rear and on 225 slicks at around 2550 lbs will do for lap times and fuel consumption on track, pump gas only.

 

[JC1378]

Just out cruising on the hwy...I commute at most 10 miles daily in town to work so my daily avg is about 27

 

[rodmoe]

Sweet with a lil prudent driving I was able to get 36 mpg with a RandyTune one 93 oct. have not checked what I get on the corn gas tune its too hard to stay out of the boost lol..

 

[hotrodst7]

i've just for fun tried to see how good of mpg i could get and was able to keep it at 40.5 at 50-55mph for about an hour, but usually i average 29mpg as i wanna go fast! lol

 

[dyn085]

I'm usually somewhere between 29-32 mpg, depending on whether I'm data-logging/having fun or just commuting. My average mph is usually between 31-33 for those that are hard-chow about this kinda thing.

 

[Xtreme545]

Got this last week cruising after fill up at around 60mph on highway

 

[SecretSquirlTuned]

I reset my MPG meter last weekend at the track and after 8 pass's I averaged 18mpg I think that could be a record.

 

[mishaioffe]

I got 40MPG average on my drive home from the Bay area to Sacramento. I was not driving slow either, around 70MPH. Love my ST!

 

[IngotST]

I'm getting 29mpg going back and forth to work which is 12 miles one way. I took a trip from Jacksonville to Orlando and got 32mpg. But I figured it with the old calculator. My avg. MPG per my dash hasn't gone over 29.2mpgs and that was on my long trip. I have 1900 miles on it now, and I don't drive it hard either, hopefully the gas mileage gets better.

 

[cxwrench]

I drove about 70 to my cousins house a few weeks ago and reset the avg mpg when I got on the freeway, when I got to his place I was at 39.6 averaging about 65-68. Should've reset that too!

My normal commute to work is very short, about 5miles...maybe 3 of that are freeway. Driving around town and very little freeway miles I normally average around 28.0.