so for starters, if I adjust the open loop load 1 and 2 to 45 between 1500 and 3500 and leave the rest "stock", and adjust the high octane fuel map to the desired 15.6 between 4o and 70 load and 2000 to 3500 rpm then, this should be a good starting point?

As what I am trying to accomplish is just increase the cruising mpg, as i am always between 1500 and 3500 driving around town/highway cruising.

Thanks guys!

 

Once the car is set to stay in open loop during cruise conditions, then the fuel maps are what need to be adjusted to change AFR. There will be some day-to-day variability in AFR, and in my experience, the AFR goes pretty rich during light acceleration in cruise conditions.

 

any input on my starter map?

I took a log today of idle and normal cruising conditions and load never goes about 55, and is typically around 20-30....

 

there are a number of tuners who have worked out specific values for open loop load and open loop tps.
I took another approach, zeroed all the loop maps. Then entered new values in the fuel map.

On my map the values up to about 4 k rpm + or -, to 90 load (different computer, months ago) needed to have values way lean. Something like 16.3 to 17 .6, and it took a number of logs/ adjustments to keep the afr where I wanted it. So it will not be a logical looking or smooth looking map once you are done.
As MRFred said in some instances the car will want to go back rich, so I leaned those cells further. Seems to work.

 

did similar on mine, mine is lean even under vacuum acceleration so around town driving has also improved in mileage, i had to reduce timing from my pre-cam map to my new cammed map. it didnt like the large amounts of timing i was running, 42+ degrees in sum areas

 

I had been playing with this open loop trick for a month and been monitoring my IPW. I noticed that despite running lean at 15.6, the IPW at idle is still the same as before. And since there's no fuel trim adjustment, I believe I may not get any better mileage ?

I set my open loop load at 500rpm to 20% and 1000-3500 at 45%

So far, I've not seen significant saving Am I missing anything out ?

 

Some hints:

1. Log Lbs/Min. This can be done either directly or via interpolating via ([Load]/95*[RPM])/454
   
2. Log Gas Mileage. For gasoline, it's (28.01*[AFRatio]*[Speed])/([LbsMin]*272.16)
   
3. Try to match up your Fuel Maps with actual Wideband readings using the MAF scale adjustments (this will take some time, my settings probably won't work for you):
   

I've been getting 30mpg highway, and the logging method above matches this.

 

I don't really hit the highway much. In town driving, I'm getting 16mpg and i try to do an average of each drive, getting 14 (short drive) to 19 (longer drive).....

Best I did in one drive was 23

 

Also, evoscan uses IPW as parameter to calculate the Fuel Consumption, vs in this case, using the air flow (lbs/min).

Question: Which is more accurate ? Since IPW is ultimately the amount of fuel squirted into the cylinder ?

I just run a comparison (taking the average of the entire log)
Using EVOScan (IPW based calculation): 19.52
Using your formula: 23.05

Now, that's making me happy ... BUT which is more accurate ?

 

Correction to your Lbs/Min, it should be
([Load]/95*[RPM])/454

 

Thanks silverstream... didn't scroll far enough to the right in my XML !

 

So, what's the difference between IPW based FC calculation vs Airflow calc ?

 

Why would MAF scaling improves mileage ?

 

Someone I knew did this after reflashing the car. He had an SAFC to pull fuel out at part throttle only where the car would see extended cruise times, like 3-3500rpm. When we put the car on the dyno part throttle in that range was 19:1, I thought it was kinda funny. We did get 35mpg cruising to Ocean City though...nothing bad happened to the car.

 

Well, talking abt which, similarly, I was on SAFC before moving to ECUFlash.

With SAFC, I do see significant improvement in consumption. But that soon got "overwritten" as I believe the fuel trim compensated it. But for the first and second tank, I do get as good as 20% ! My settings were just around -7%.
That's ALL by tricking the Airflow reading.

After coming into ECUflash, I am getting lots more power with ignition and fuel adjustment, BUT no way I can the above 20% ! Applying the above -7%, I guess I am running at 7% less of 14.7 at cruise, which is 15.7, and I am running open loop.

Why aren't I getting as good mileage as a SAFC can deliver ?