Cleo has become an MPG project

[Philip1]

She is actually efi but what I was getting at is I know how extremely lean conditions feel. The paint can remark was a comment about the pistons they are huge.

[Philip1]

Just today short sample 34.5 mpg for the last 20 miles

[pgfpro]

Originally Posted by philip1

She is actually efi but what I was getting at is I know how extremely lean conditions feel. The paint can remark was a comment about the pistons they are huge.

Oops
Sorry I thought you were running a carb.

Then I would go with your original plan and start taking away fuel until you notice a slight misfire then add some fuel back to get it to run smooth as you said.

[Philip1]

I think I have a lot of ignition I can add too, if needed.

[Philip1]

I've written a tune with fuel pulse widths reduced by 5ms in the 1400-3200rpm and 18-48% load range and ignition advanced 3 deg there too. I'll test it out tomorrow.

[DRW]

Originally Posted by philip1

I've written a tune with fuel pulse widths reduced by 5ms in the 1400-3200rpm and 18-48% load range and ignition advanced 3 deg there too. I'll test it out tomorrow.

"5 ms"? Is that right? Maybe I'm used to the injector time scale on my car, but that sounds like a lot. Are you sure the units aren't Us?
ms= millisecond=0.001 second
Us= microsecond = 0.000,001 second
What's the stock injector pulsewidth in the load/rpm range where you plan to make those changes?

[Philip1]

Tbh I have no idea what units they are using but I reduced the number by 5

[Philip1]

Here are screen shots of the maps the first is the stock map with the affected area highlighted I haves also highlighted the altered map.


stock map




Altered map



Hmmm looks like I went 7 instead of 5 oh well.

[DRW]

Ah, I see. In that case I'd simplify and convert into %. For example, 117-7=110.
117/110=6% change.
Assuming the stock map is aiming for stoich 14.7 AF ratio, removing 6% should put it around 15.6 AF ratio.
math;
14.7 parts air mixed with 1 part fuel =14.7:1
14.7 parts air mixed with .94 parts fuel =15.6:1 from removing 6% fuel.
14.7/.90 = 16.3 AF ratio from removing 10% fuel.

[pgfpro]

Looks like a raw number scale.

So what DRW did should give you how much fuel you've taken away.