Alright I am working through the process of creating a true instant MPG meter.   

 

 

In theory, I love that word, we should be able to know how much fuel is being burned.   We know commanded duration, we know speed, we know rpms.  

 

Below is the rough draft #1 for my testing, I am not concerned about it being %100 accurate. 

Quote

 

building the equation

 

A 4 stroke 6 cylinder engine should have 3 power strokes per rev, so power strokes, or injections, per minute will be RPM * 3. 

 

Mph to MPM would be MPH / 60 = miles per minute

 

we need to get stroke converted into gallons. 3785410 mm3 = 1 gallon

 

The last thing we need is a MM3 of fuel per stroke in the vp44.  

 

After a good bit of reading I have come to the vp44, in stock form, producing 125mm3 of fuel per stroke max.  

 

Now we throw some fuzzy math at it and say that duration % is linear to stroke. 

 

 

If we plug that equation into excel and input duration, rpm, and mph into it we get output mpg's that match, considering fuzzy math, a vp44 truck.  

 

IE: stock, 55 mph, %20-%25 duration 1460 rpm = ~22-24 mpg in a perfect world.   

 

 

So my Question is when it comes to injectors in the VP44 system.  If the vp44 can produce 125mm3 of fuel per stroke in stock form, what happens when you increase injector size?  Does having larger injectors mean the vp44 will produce more fuel, IE 200 mm3 of fuel?    Or is the 125mm3 the vp44 is spec'd to produce a constant unrelated to the injectors?  

 

@jlbayes @mopar1973man @carbur8tr and anyone else that has an input.

well I am getting it dialed in.  I think I am close.  My trip into work this morning is 8.9 miles mostly 40 mph with a few stops.  If I just DD my truck to work and back I average 15ish mpg

 

 

so 9 miles / 15 mpg = .6 gallons burnt.  I think the quad was saying I burnt .65 or something.   I have since adjust my offset down from %155 to %140 as my instant mpg was a few mpg low for a stretch of 55 mph.

Here is what Dash Command is providing... The second page (tab) is showing the use of gears and how long I used each one and also if I used the wrong gear too for how long. Still this is uncalibrated I'll be doing the calibrate process when I get down to Ontario, OR today.

 

 

My numbers are bit low being I did tow a trailer this weekend. I hauled my ATV out for afternoon ride before the all week long rainstorm came along. 

 

 

I really doubt you going to have this much info... 

I won't match that amount of info, but that info is not based on the actual fueling command