When I add a little too much E85 to my gasoline mix my AFR runs lean.
Do you guys know if this is due to the Injectors or the Fuel Pump not supplying enough fuel? I wonder if the JMTC HPFP is the real deal and will help with fuel needs. What do you guys think?

http://www.jmturbocoopers.com/Mini-C...rade-HPFP.html

 

Definitely don't think the HPFP is the weak link in your system, but I'm curious what others say. I don't think I've seen an R56 that has needed to upgrade the fuel delivery system, and that includes the international cars on the other forum. This isn't true for the R53s that do need upgrades (but that's usually when they are making really big tuned power).

Maybe the E85 is enough, but I doubt it (since it sounds like the mix you're running is a lot less than E85).

 

I guess a follow-up question is what is lean? Do you have some logs plotted that you can post? These engines run leanish generally.

Also, what fuel mix are you running?

 

I just read my Scan Gauge.
I usually mix about 3 gal E85 and 10 gal 91.
For example if I do a gear pull like 4th gear at 2,000 rpm WOT.
It will run lean. AFR Will go 14.9>15.7>16.9
I know it takes more E85 to make the equivalent power of 91. So are my injectors not supplying the proper fuel or is it my fuel pump not supplying enough fuel. Was my question.

 

I see what you're saying. I don't believe that's enough ethanol to overwhelm the fuel delivery system. My guess is this about the interaction of your JB+ and the extra boost it's producing with the E85.

You can find calculators online to check your injector duty cycle. I expect you'll find you aren't limited by them, but I could be wrong.

 

Look at your fuel trims. Is your LTFT maxed at 33% (may not be exactly the right number)?

Sent from my XT926 using NAMotoring

 

I'm not exactly sure how to calculate fuel trim.
Does the scan gauge do that? Lol
Amateur over here.

 

Running lean w/ E85 is just a tuning issue. I've not seen any signs of fuel pressure dropping that would indicate some fuel limitation.

 

I got the JB+ cranked all the way. That is probably the issue.
DME is probably wanting more boost or something

 

What AFR are you seeing towards the top of the gear?

 

It just runs lean on low RPM. But it fixes itself on top end.
Say 4th Gear WOT 2,000-3,500rpm (14.9>15.7>16.9) or something.
Then 4,000-6,000rpm (14.0>13.2>12.3)
So it just runs lean on low end. I thought it was too much E85 or something.
But I prob have the JB+ up too high since it's at 100%

 

The DME can compensate with in a 33% fuel trim range. With the extra boost being asked for with the JB+ and the E85 that can easily run out of room. The fix is to add a fuel mass sensor control to rescale everything for the E85. Took a few months off from the MINI but I'm actually looking at that sensor now to see if we can manipulate it. Would allow us to run more boost & higher E85 mixtures.

 

Sounds like a great idea!
Probably something the JB+ wouldn't be able to do right?

 

I'm using a JB4 type system currently to evaluate the tuning end. If it works out and we wanted to implement this on customer cars I'd then have to figure out the best way to package it. It could be a seperate device you add in addition to the JB+ or could be a replacement harness that replaces the JB+. That would depend on a few technical factors yet to be determined. But in any event it's simply not practical for customers to reach this sensor connector. It's under the intake manifold. So it would require cutting a sensor wire in a discrete area to patch in.

 

Ok cool. Hopefully all works out.
I wish to run E85 one day without doing all these mixes. Or even just do a much higher mix