As far as I know the MPG screen is pretty close since you have to scale the injectors to make the fuel trims balance out. It could be the last test I did is a slight overall downhill but that should only account for ~2 mpg on the readouts. My next series of tests will be adding together runs both directions and just cutting out the part where I get off and back on the expressway.

Changing timing at cruise only effects that area of operation, as soon as you start spooling up the turbo at 90-100% load and reach positive boost you are no longer in the 40% load area of the timing maps where the increased timing was made.

 

that's where I added my timing... 3* from like 2250-4000. 0-40 load

 

Interesting... I went into Dover De. Mitsu dealership to get my fuel recall done, uninstalled the AP, it's backroad driving. I managed 27 mpg going from 50 40, 30, mph.. a few areas of highway at 60 mph. I installed the AP with my Mellon tune with the map slightly changed as I had posted above. I was around 26.7 when rolling into town. I don't know if i'm not getting the full benefit because I don't have a more free flowing exhaust, intake, UICP, etc. or perhaps the timing could be changed in other areas to increase mileage. That's not bad mileage either way, but i'd like to get to the 30 mpg that HiBoost has gotten.

 

A laggier turbo for sure helps with mileage as it doesn't spool if you sneeze like the stock turbo.

 

now to get a real good MPG you can do a fill up and drive the whole tank out then fill up and devide themiles with the gallons i say because i was getting 38MPG and after a 12 hour trip to MI from VA i averaged 31MPG after i finished out the tank. i know it dont count cuz you have a crap load of HP compared to a reg lancer. be careful with the lean tho.

 

Question if you adjust your CYLINDER FUEL TRIM 1-4 to something like 14.9 or 15.0 instead of the OEM 14.7 would it net any gain in MPG?

Also would increasing you high octane fuel map sections where it is 14.7 to 14.9/15.0 net any gains in terms of fuel consumption?

 

no because the car will still be trying to maintain stoich.

be an interesting test thou to see if your trims change...

 

Thanks for the insight

 

I was thinking of testing those maps but never got around to it. You can easily measure a similar drive back to back and take an average of the wide band AFR's using excel and compare. You can also log the "target" AFR that the car is trying to use from the maps at any one time which may or may not reflect changes in those maps.

You can definitely alter the lower cruise AFR's by changing your closed loop to open loop crossover from the 100-120% stock down to 30% or so. This will switch you in open loop much sooner and force it to use what's in your maps. Keep in mind that even if it lists 14.7 that it may be richer or leaner than that by quite a wide margin and expect to spend many hours getting it right under all the various throttle conditions. Personally I found that it got too rich at throttle lift and a bit too lean when under light load but tweaking should resolve that.

If you have time I would say test it out, just start on the richer side and make small steps leaning it out and note what settings it took to reach stock like operation of 14.7 AFR and then once that is stable aim as lean as 15.4 and see how it goes!

 

Hmm... so you stay in OPEN loop by changing OPEN Loop Tables HIGH to lower figures? And then adjust your high octane map starting with richer I.E. 14.7 and then slow starting to bump it up in the cruise area to much leaner values.

See what I was thinking is that the Cylinder Fuel trim tables are what the ECU looks at to stay in closed loop. So in my theory... I think that you for example bump the cylinder fuel trim table from 14.7 to 15.0 @ 2500-4000 rpm up to 70-80% load, interpolate the values at highs and lows for a smooth transition. And then keep the OPEN LOOP Table High at like 90-80 load units in the 2500-4000 rpm region.

I think that would force the ECU to Try to run a closed loop system of 15.0 in that cruise area. Or just change all the Cylinder Fuel Trim tables to like 15.2 if you don't have a CAT. And see if the computer forces the car to be leaner...

I might test this today....

 

Well Clipse3GT is on the right track you need to mod the Closed Loop if your cruising your at a stable speed and load, the ECU transitions into Closed loop the second you hammer the throttle its going to go into open look ignore the requirement for Stoic and give you the power your demanding... Has anyone data logged when the computer will switch from Closed to Open while trying to cruse? That should help you all out as well.

 

It depends... I have my open loop tables high and low set much lower than stock... Since I know I cruise on the highway between 40-80 load around my area. Stock are like 120-140 load, which is very right forcing you to stay in closed loop for a bit longer. I prefer to have the open loop set a bit lower so when you do hammer the throttle it goes and uses the high octane map, which I have setup for a lean boost. So I can get about 22psi by 3000rpm already of boost.

But I think if you adjust the fuel trims of each cylinder for leaner in the cruise area, it will make the system use those values for closed loop. This way you do not have to be in open loop all the time and still get better gas mileage.

EDIT:

Something like this looking...

 

Nice Kris, I'm excited to see test results =)

 

I'd be really surprised if it works like this, because the stock narrowband O2 sensor can only "see" 14.7 AFR, rich, and lean. The ECU really has no way to target any AFR other than 14.7... unless the stock primary O2 sensor is a wideband

 

I am not so sure.... Then why is each Fuel Cylinder map the same 14.7 and adjustable. I think these map may adjust closed loop fuel trim. I will try to test this with a stock IGN map and see if what my closed loop looks like.

I dunno... makes sense to me. Otherwise what is the point of those tables...