I've tuned my WGDC tables to use the turbo very little under 48% throttle. At 39% throttle, I have my WGDC tables set to 50 - 55% down low (idle to about 2000 RPM), so i get get off the line w/o WOT when I want. At 28% throttle, the WGDC doesn't go over 20% from idle and tapers to 0. Below 28% throttle, my WGDC is practically 0. In the cruise range, the WGDC is mostly 0's.

From looking at my logs from daily commute style driving, I almost never go above about 25%. At steady state cruise, TPS is almost always in the 20 to 25% range even w/ cruise control engaged. I have no problems reaching 30MPG going to work (all down hill), but coming back I can achieve ~20MPG if I'm gentle the entire time (all up hill)...

 

You won't be able to go lower boost then the wastegate setting.

Also, in theory if you ran 0 psi, the turbo would then become a huge restriction and your MPH would drop like a rock, not to mention you could probably barely get out of your driveway.

 

Best thing to do is trade it on on a NT Ralliart.

 

It's not all about how much boost you are running. On my trips from KC to Colorado I will start to hit a lot of elevation changes and If I try to maintain a high speed (70-80mph) on a larger incline I will only hit maybe 1-2psi but there is enough load that my AFR's go from 14-15 to 12-11's. On one tank of pump gas I only got 180miles and never went over 5psi.

 

yea thats what im getting between 180-200miles on a tank

 

Are you saying I cant get out of the driveway because of the AWD needing so much power? is this why the GTS and the ed/es get better mileage since they're FWD is what im assuming is the obvious reason.

cause if you look at the outlander sport it has the same block as us, which is a 4B11 but its front wheel drive and is getting 25/31 which is what im makeing running on lower boost number. The AWD CVT gets 24/29 which is still reasonable to what im making since we're basically the same on the AWD department and engine, just that I'm running a lil more power with being 9.5PSI of boost always being on when I floor it.

 

I'm averaging between 240 to 280 per tank in Dallas depending how i drive but I do mostly highway except when the highway becomes a parking lot.

 

Better yet if you seek more MPG, just trade it for a Prius

If you seek more smiles per drive, just drive it like you stole it

 

If you want better gas mileage on your Ralliart, tow it.

 

If I were completely oblivious about the current gas prices, I wouldn‘t have bought a ralliart but a used ‘00 Nissan GT-R or something for the same price.
Retarded comments about buying priuses cause you want to switch between power and eco.
Everyone aint millionaires ffs ...

 

What he is saying is that your talking about a low compression 2.0 liter engine with a sock stuffed in the tail pipe if you try to run it at zero psi all the time. A high compression NA 2.0 would crush a zero boost 4b11t in both economy and power delivery.

The engine is designed to run with boost pressure, hence the reason for the low compression. If you take the boost out of the equation you are left with a low power engine with a very restrictive exhaust (since the turbo is not putting energy back into the system at that point the hotside is nothing but an exhaust restriction).

And yes, the awd system introduces more parasitic losses than fwd or rwd alone. And the RA is heavier because of the awd system.

There are things that can be done within reason to increase mileage (most have already been mentioned), like running switchable maps for econ and power... the econ map would have the wastegate duty cycle zeroed out so you only get spring pressure... you would probably set the open loop thresholds so you run open loop almost all of the time so you could tune the cruize area's to best economy afr and keep the boost area a good bit leaner.... like 13.2:1 max...

The other option is to tune the cruise areas in open loop and deaden the boost control tables under say 50% throttle (also already mentioned).

A third is to combine either of the first two with a larger turbo that has a higher boost threshold and less restrictive exhaust side.

Lets not forget the easiest option, stripping as much weight as you can out of the car.

At the end of the day... I think it's gonna be a stretch to get more than a 5mpg increase on a tank with mixed city hwy driving unless you drive like a grandma... and if it is that important to someone, they bought the wrong car to start with... they should have gotten an old jetta diesel or a new tdi that both get 40+mpg without even thinking about it.

 

I get about 240-260/tank here, mostly city driving like an old woman, but thats only when I can force myself to stay out of it for over a week at a time.

 

ha ha i still have the same 3/4 tank worth of gas and its been over a month so i am getting amazing MPG. so my advice to you is if you want to get good MPG just take your motor out of the car but i am usually lucky if i get 180 miles to a tank

 

It's just the f---ing gas prices playing with our heads. It's 15 sek/l here now in Sweden, converted to $ that's like 2,27$ per liter or ~8,59$ per gallon

 

Let's not forget that this car IS turbo charged, and turbos force air into the intake. So, when you shut it down not only does the exhaust turbine become an obstruction to exhaust flow, the intake compressor become an obstruction to intake flow, also. Thereby, compounding the issues of not being able to develop power, and in theory potentially lower MPG beyond what's already being considered "poor" (on top of not making enough power to get out of its own way).

An engine is basically an air pump regardless of whether or not it's forced fed. When you obstruct the intake and exhaust sides of an air pump the volumetric efficiency drops through the floor.

On a NA car it's a ~generally~ accepted rule that greater manifold vacuum levels during cruise = greater fuel efficiency. On our turbo charge cars, it's not necessarily true because after a certain point the turbo becomes an obstruction on both sides and as a result kills the efficiency.

As Bryan already mentioned, the turbo has to spin in order to achieve the best efficiency. As you and several others have implied, tuning of the respective areas is necessary to achieve it.