Coyote Injector Settings

[schaid]

So I've spent the last couple days downloading the various tunes I've got from various tuners. A question has risen during this:

How the hell are injectors set for the coyote????

According to just using the flow rate hi/low, which seem backwards to me these are the numbers as follows:

Stock:
Low: 0.0167999 in lbs/second...which if calc'd out comes out to 60.4764 lbs/hr
High: 0.0125200 in lbs/second..again the calc comes out to 45.072

As most know, the stock injector size for the coyote is 24lb/hr, if my information is correct.

So with this observation I dug further.

My findings

Settings for 47's
Low: 0.0178260
High: 0.0169319

Respective calculations are 64.1736 & 60.95484

Settings for 80's
Low: 0.0281830
High: 0.0208770

These come out to 101.459 & 75.1572

Knowing our fuel pressure runs @ 55-56psi I looked into my multipliers...they add between 5-19% to the flow rate? I see no fluctuation in my fuel pressure from normal driving to wot. I've got a digital fuel pressure gauge just before my rail.

Are these tables inverted? Is low supposed to be high and high supposed to be low? Some clarification would be fantastic.

[schaid]

Somewhat found my answer with some more searching although more questions are raised.

I've got the frpp 80's...basically the siemes 80's, I have the settings verbatim from the calibration sheet...my problem with this:

The settings are for 39.15psi, I've got 55psi, so do I need to increase all settings by 16% to get the proper settings? I got the 16% by taking the flow rate of the injectors @ 39.15 and assuming at that point frpp has them at 80 although siemens has them rated at 80 at 43.5psi.

Where are all of these numbers derived from? I now get the hi/lo settings. The labeling is a bit misleading, maybe low slope and high slope would be better than injector flow low and injector flow high.

[02reaper]

I've been wondering the same thing also..

[schaid]

I've been wondering the same thing also..

Ok good. I'm glad I'm not the only one questioning this.

[schaid]

Anyone?

[02reaper]

Hopefully Eric will chime in when he gets some free time and explain this since nobody else is coming forward.

[schaid]

That's what I'm hoping for. I know he and I struggled through setting up the frpp 80's last year with my car. There were multiple attempts made to get them to idle correctly and the ultimate outcome was a min pw of 0.

[Eric@HPTuners]

The low slope number is supposed to be higher. The values are then adjusted by a multiplier based on the measured/inferred pressure.

[schaid]

I was gathering that. Now should I adjust the values in the low slop high slope tables based on 80's @ 55 psi same with the multipliers? Slide them so the 1.0 multiplier is even w/ 55psi as opposed to 39? Then just calc out what the multiplier should be below and above?

[schaid]

So I decided to go for my theory...the result:

An amazingly smooth idle.

I only changed the references. If anyone wants/needs more elaboration I'll gladly share specifics.

[02reaper]

Please share all that you can.

[Japeatr]

good to know... so you scaled by a percentage factor of the pressure?

[schaid]

With my 47# and stock these didn't seem to cause any issues. The issues only arose with the 80's. I'm sure the same theories could be applied:

High Slope, low slope, offset, break point, and min pw all stay as they are outlined here: https://www.fordracingparts.com/part...-9593-lu80.pdf

I set the multipliers as follows:
High Slope:
39 - 0.72
50 - 0.87
55 - 1.00
60 - 1.13
65 - 1.19
70 - 1.20

Low Slope:
39 - 0.71
50 - 0.87
55 - 1.00
60 - 1.04
65 - 1.23
70 - 1.22

Break Point:
30 - 0.71
40 - 0.88
55 - 1.00
60 - 1.08
65 - 1.12
70 - 1.31

Offset Multiplier:
45 - 0.7149
50 - 0.6306
55 - 1.0000
60 - 1.0908
65 - 0.9903
70 - 1.1848
75 - 1.2383

Idle, drivability, and decel have all smoothed out. Near stall...non existent. More steady idle. I am working on something else that when I get near completion I'll outline what I've done there as well.

[lxlaw]

So you entered the info based on the multiplier of 54.95 psi..???

[schaid]

I changed the reference point so that the multipliers @ 55psi would be 1.00...which is the fuel pressure the coyote runs at. You can accomplish it by changing the values within the tables as well.

[lxlaw]

So...you entered the data based on the pdf with the multiplier at 54.95...then rescaled the multiplier in HP..??

[lxlaw]

Can you screenshot the table you're talking about..??

[schaid]

I set the multipliers as follows:
High Slope:
39 - 0.72
50 - 0.87
55 - 1.00
60 - 1.13
65 - 1.19
70 - 1.20

Low Slope:
39 - 0.71
50 - 0.87
55 - 1.00
60 - 1.04
65 - 1.23
70 - 1.22

Break Point:
30 - 0.71
40 - 0.88
55 - 1.00
60 - 1.08
65 - 1.12
70 - 1.31

Offset Multiplier:
45 - 0.7149
50 - 0.6306
55 - 1.0000
60 - 1.0908
65 - 0.9903
70 - 1.1848
75 - 1.2383

Is it that hard to read these and input the reference points? You click on the margin and you can change the references. Not trying to be a dick, but I outlined exactly what I did in the post I quoted this from. As stated in THAT post, there were no issues w/ stock or 47# injectors. Issues only arose with my setup with a 5" intake, cobra jet intake manifold, twin 60mm tb, 80# fuel injectors, and an otherwise stock motor. There are tuners out there that refuse to use these injectors stating they are junk and "untunable", well at this point I'm begging to differ. They are very tunable, so long as you know that the multipliers are going to jack the slope up by 19% based on the fuel pressure. With the settings I've got I should be running right at the low/high slope tables. I'm having to work with other tables to get everything "back in check" but that's not the end of the world and nothing some histograms, a spreadsheet, and a couple drives around the block haven't all but cured.

I'm really not fond of repeating myself. These cells are found under the "Engine->Fuel->General" tab.

[lxlaw]

Thanks...sorry to inconvenience you...

[schaid]

It's not the inconvenience, the information was already posted...in this thread. It was the post right before your first post.