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Discussion Starter · #1 ·
After having read some of the excellent threads on our experiences with mpg;
I would like to suggest we contribute to a simple, generally agreed upon consensus of driving habits, add ons, you name it, to maximize mpg of our rockets. All based on personal experience. This will hopefully keep this thread shorter.

In general ( STI and any car ), these things below are known and agreed upon:
skip shifting= get to taller gears without bogging.
lighter oil weight, probably synthetic.
higher tire pressures.
reduce drag, closed windows helps though a pain.
off with AC.
higher altitudes seem to improve mpg?
use cruise control.
remove one or both cats ( I am not sure on this )

now some STI specific ideas:
running DCCD in manual/full rear for highway runs
Cobb can it be set to improve mpg via more lo torque etc?

Please add to this incomplete list.

I have been getting lo mileage because no steady highway speeds and crazy for acceleration!!
 

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Discussion Starter · #3 ·
boost being, 3500 rpm up?

boost being, 3500 rpm up?
Assuming I am resisting the torque/higher rpm rush
Does removal of a cat help?
Does the differential in rear position ( ?) help?
CAN a Cobb help make lo torque which in turn helps
keeping out of boost= lower mpg?

If 40lbs in Front tires, how much in rears?
40 throughout yields what?
 

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Welcome, and there's already a mileage tips thread somewhere.
 

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october said:
CAN a Cobb help make lo torque which in turn helps
:lol: Cobb is a company that makes aftermarket parts for our cars.

1.Shift at 2200 rpm
2.leave it in manual/rear dccd mode
3.drive slow on the freeway(air resistance kills MPG)
4.Stay out of the throttle.
 

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Discussion Starter · #7 · (Edited)
thanks

The diff mode you refer to is, shall I call it, "South" on the dash board, closest to the floor?
That is OPEN, right?
And locked is? just south of auto??
Do some claim that open or furthest "south" is best for mpg?

Sorry for the compounded dumb questions
 

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thanks for the questions... I was wondering the same about the DCCD... is all locked up the best for "spirited on road driving" (at the expense of mileage then)

Thanks!
 

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no all locked up is not the best for spirited driving. i would keep it in auto. lock is best used in bad weather.
 

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welcome
 

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Discussion Starter · #14 ·
6000rpm, no turbo...yes but..!

I found myself saying at first, Oh, ok, no boost AND hi rpm is not mutually exclusive, then i thought about it- How? Could you enlighten me please? more details?
"Thanks. I'll take this off the air" (talk radio) lol
 

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october said:
I found myself saying at first, Oh, ok, no boost AND hi rpm is not mutually exclusive, then i thought about it- How? Could you enlighten me please? more details?
"Thanks. I'll take this off the air" (talk radio) lol
Think in terms of engine load rather than rpm. Remember rpms don't spin a turbo- exhaust gas does. Clear as mud?
 

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Discussion Starter · #16 ·
San diego? Me too.

I guess so ( clarity ), but it's still a little murky.

So if I gradually increase rpms, the waste gases have a chance to expel, reducing pressure, leaving turbo unscathed.. something like that?
so in practice, press throttle gently, not too deeply all at once? That is usually what i do.

Where do you get car serviced- who do u trust?
 

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october said:
I guess so ( clarity ), but it's still a little murky.

So if I gradually increase rpms, the waste gases have a chance to expel, reducing pressure, leaving turbo unscathed.. something like that?
so in practice, press throttle gently, not too deeply all at once? That is usually what i do.

Where do you get car serviced- who do u trust?

Boost threshold= minimum rpm you can reach full target boost

Spool= how quickly you can get to target boost when rpms are above boost threshold.

Below the boost threshold and prior to reaching the target manifold pressure the waste gate is essentially closed in order for the turbo to spool up quickly. As it approaches its target boost the wastegate starts opening and will maintain what ever opening is needed to maintain the target boost pressure.

Keep the car a an even pace and use small throttle changes and its easy to stay out of boost.

Does this help you understand?


If you have a boost guage in your car I suggest varying your throttle inputs to keep you out of boost. Avoid getting into boost for too long and a horrible thing might happen...





...nothing except you'll castrate the beast and live a long boring very civic like life!





edit: I just realized you are in SD so I added this: I service my car myself, if you need some help or wanna hit the twisties hit me up.
 

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for better mpg make the car lighter. also, a cf driveshaft and lighter wheels/tires will help alot.
 
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