So I ask myself..."What kind of fuel economy can I get?

turboleg · Post by **turboleg** » Wed Apr 30, 2008 2:22 pm

Basically I have a few weeks left of heavy commuting before I start my new job that’s very close to where I live. So while my commute is still over 100 miles per day I was wondering what kind of mileage I could possibly get with my 1993 Subaru Legacy L FWD. So over the past few weeks I have adjusted my driving characteristics and really kept an eye on average fuel economy.

My driving is mostly country and dirt road driving with about 10-15 miles of express way per day. Temperatures have ranged from 20-70 degrees F since I have began doing this little study, average temp is probably around 55-60 deg.

Here is a little background on the car:
-93 Legacy FWD Sedan 5sp stock other than the 2.5RS suspension
-204,000 miles on the clock
-When I purchased the car at 140,000 miles I pulled the oil pan to find around 1/4" of sand/silt on the bottom of the pan, I did nothing more than clean the pan out.
-I get a horrible tapping sound from the passenger side head on cold mornings
-I burn about 1 quart of oil every 1,000 miles
-I have all of the maintenance records from the PO which indicates that the only mechanical engine work ever performed on the car was a front main seal (excluding standard maintenance).
-Standard tune ups only completed since cleaning the oil pan out.
-Soft winter treads running at around 32 psi @ 50 deg F ambient

With a few minor changes in my driving habits:
-Smooth acceleration from stops
-Shifting at or below 2500 RPM when possible
-Not coming to complete stops when it is not necessary
-Eliminating unnecessary breaking (if you concentrate there is a lot of it)
-Clutching/going to neutral during some of the major down hills I encounter
-Minimizing idle time before and while driving
-No longer using cruise control
-Doing no more than 10 MPH over the speed limit

After all is said and done over the past month (which is about 5-6 tank refills) my average fuel economy is approx. 34 mpg and it’s very consistent. Knowing this I have no fear of letting my trip meter read 400+ miles before I refill the tank.

I will add that one of the things that spiked my interest was an "all highway" trip that I took two years ago with this car. I kept thinking that I read the trip meter wrong when I calculated my fuel economy. The all highway driving calculated out to around 36 mpg. I don't make many of thos trips, so I could never come to agree with the calculation. This kinda helps me believe it.

Bottom line......you paid how much for your gasoline powered 32-34 mpg Toyota, Ford, Nissan, Honda......???

evolutionmovement · Post by **evolutionmovement** » Wed Apr 30, 2008 3:21 pm

Drive like a wuss in anything and you'll get great mileage. I drive like a dick and with the A/C on and a couple dudes going over 90, several miles of stopped traffic, and a couple sprints over 100, I still got 28 mpg in the Mazda3. Revised sticker says 30, I believe, and I've beaten that just by driving like a normal person. I'm hoping for over 100 driving the car I'm building like a wuss, in the 80's for relatively normal driving.

turboleg · Post by **turboleg** » Wed Apr 30, 2008 5:06 pm

I also have over 150lbs of stereo equipment in this car

32 MPG in my normal spirited driving fashion

smh0101 · Post by **smh0101** » Wed Apr 30, 2008 5:24 pm

Ahem... 18 on my last tank... (11lbs boost)

But about 22 on this tank keeping it in vac at all times.

turboleg · Post by **turboleg** » Wed Apr 30, 2008 5:30 pm

smh0101 wrote:Ahem... 18 on my last tank... (11lbs boost)

But about 22 on this tank keeping it in vac at all times.

Are you moded without EM?

My project car is currently using the 4.111 5sp with a otherwise stock EJ22T (I have cranked it up to 11psi on this setup). I hang around the 25MPG area with my foot to the floor most of time. Like I said I drive a lot of back and dirt roads and stock ej22Ts are slow.

smh0101 · Post by **smh0101** » Wed Apr 30, 2008 5:50 pm

No EM yet. Exhaust IC Boost

Murphy · Post by **Murphy** » Thu May 01, 2008 12:08 am

how does no using cruise control help? i thought that was always one of the good things about it is that it kept you at a steady pace

smh0101 · Post by **smh0101** » Thu May 01, 2008 1:46 am

The problem with cruise control is that it will do whatever it can to maintain a steady speed. So if you have it set at 80mph, then you hit a hill it will accelerate as hard as it has to in order to keep speed. If your controlling it you can let off for a little bit and lose some speed BUT maintain mileage.

You have an auto tragic so you cant do this... But if I have it set at a speed then I pop it out of gear without pushing the clutch or the brakes the car doesnt know that... and it keeps trying to accelerate to maintain speed and it will hit redline if need be.

I can definitely get better mileage than cruise...

I can keep it in vacuum the entire time... however the ECU will utilize all 11lbs of boost if needbe... thus killing your mileage.

Richard · Post by **Richard** » Thu May 01, 2008 2:59 am

I get 20 mpg, but my knock sensor, purge solenoid, and IAC are on thr fritz.

asc_up · Post by **asc_up** » Thu May 01, 2008 9:01 am

Hmm I get about 18-19 MPG, but I suppose that could be because of 14psi and driving like a jackass.

Even when I try not to drive like an ass, I still only get about 21 mpg (and yes, my plugs, wires, 02 sensor, knock sensor, etc. are new).

93forestpearl · Post by **93forestpearl** » Fri May 02, 2008 12:57 am

I get 24-25 in the winter on the highway and creeping up to 29mpg in the summer. Wiseco pistons raise the stock EJ22T compression to 8.5:1. Larger turbos actually help too. They make you have to work a little harder for boost. Also, I run about .5-.8 pts, lean with up to 48 degrees of timing. Its tricky trying to make it not surge on the highway like that, but my wallet likes it even if the EPA doesn't.

entirelyturbo · Post by **entirelyturbo** » Fri May 02, 2008 3:33 am

I once managed to get 34mpg out of my Legacy for a half-tank on the way back from the Dragon a couple years ago. Hasn't happened since. I don't know what I was doing so exceptionally.

No matter, though. I've gotten 39mpg out of my Honda on the highway, and on my trip to Atlanta next week, I'm going to attempt to get 40mpg or better by leaving early in the morning and just setting the cruise at 70mph on the highway.

douglas vincent · Post by **douglas vincent** » Fri May 02, 2008 5:54 am

No CELs and what do I get?

16 mpg.....

In my NA.

NOTHING is fucking wrong with it! Goddamnit!

smh0101 · Post by **smh0101** » Fri May 02, 2008 5:59 am

Now is that the super and turbo charged car with an NA block or the totally NA car?!? lol jk

douglas vincent · Post by **douglas vincent** » Fri May 02, 2008 6:44 am

Totally NA daily driver.

93forestpearl · Post by **93forestpearl** » Fri May 02, 2008 9:19 am

hmmm. You've done all the basics I assume? Can an O2 sensor act funny before it actually throw a CEL?

asc_up · Post by **asc_up** » Fri May 02, 2008 9:30 am

93forestpearl wrote: Can an O2 sensor act funny before it actually throw a CEL?

Yes. I changed mine because I was getting 13 MPG

Once I changed it I went up to 19 MPG. It wasn't throwing a code at all.

smh0101 · Post by **smh0101** » Fri May 02, 2008 9:31 am

huh... i may want to check mine then...

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So I ask myself..."What kind of fuel economy can I get?

So I ask myself..."What kind of fuel economy can I get?