Guys,

Don't flame me for this. Some of us really don't need all the power 80% of the time but would like to have it accessible when needed. Is it possible to turn down the boost to yield better MPG figures? I know that the stock injectors are large and the ECU is designed to run at certain boost settings. Is there a way to thwart this? It would be a dream to get 26 to 27 mpg on the highway while cruising on low boost.

 

The car isnt really tunable yet, a boost controller could limit your boost, but might be a good idea to just stay off the gas?

 

So if your on the highway in 5th gear your usually not in boost unless full throttle. So wheres the problem????

 

If he is on the highway in 5th gear going speed limit,70-75 per hour On An EVO-X
He is at 3500+ RPM, Boost is a slight tap on the gas.

Its not Like the VIII anymore.

 

Use your right foot. It's called throttle modulation. Get a boost gauge so that you can see how much you're boosting so that you can modulate the throttle accordingly.

OR, if you want to get ghetto.... you can redo the vacuum lines that make up the stock boost control system. Basically, create a new path that bypasses the boost solenoids so that the wastegate will see actual manifold pressure. And then stick in an electric solenoid or something that you can open and close from inside the car. With it closed, the stock boost control system works and everything is merry. You open the solenoid/valve/whatever, it bypasses the stock boost control system and the turbo runs off of wastegate pressure. If it's like the VIII/IX, then 11psi.

 

im not sure this would achieve your goal. Even cruising on a flat road, this xar is running 25mpg. The issue is weight and the current fuel management. When we can lean out the cruise afrs a bir, we can get better milage

 

Just ease off your gas pedal. Turning down the boost will only save you gas near/at WOT.

 

First thing to improve millage is back it up into normal mode which alters the maps and response for higher efficiency. The biggest thing to do to save gas in a turbo car is alter how you drive. Getting into boost eats gas, so work on being smooth with he gas and constant. Turning down the boost wont help unless you are gasing it heavily in which case you mileage will not be good anyways. Other ways are products like the access port once released which allows you to change maps on the fly with options like having a high mileage/low performance map

 

Once reflash tuning options become available you should have the option to drop to open loop sooner and tune the fuel map for better mileage. Plus what the other have said, throttle modulation will kill your mileage as will on boost time.

With the option to drop to open loop sooner you could lean out the low vac / low boost areas and the high vac cruise areas.

 

The boost controller would do absolutely nothing with your gas mileage on the hwy for the simple fact that when you are crusing at 70-75mph you are hardly building boost. It will no affect the gas mielage at all, the stock ECU does its job well and on the hwy and cruising at 75mph the engine load is low.

My tips:

Have your tire pressure correct at all the time
have your air filter clean the whole time
Roll the windows up


Carlos

 

On the highway cruising your in closed loop fueling....adjusting boost will do nothing....

 

you can find something else that has better gas mileage maybe?

 

i'll trade u my 08 lancer for ur evo x.. it will get better mpg!!! LOL

 

Drive an H3 for a week, then realize the gas mileage on an evo is great.

 

really. if you get a PERFORMANCE CAR you shouldent have to worry about mpg.