2015 coyote fuel trims with 47# injectors / speed density

[dsandahl]

I have a 2015 coyote with 47# LU47 FRPP injectors, 2018 intake, GT350 TB and GT350 CAI.

I am experiencing large fuel trims. I first followed other post recommendations to use the injector data from the Roush tune. That resulted in short term fuel trims hitting +25% in higher load/rpm conditions.

I then switched to the Ford datasheet values and trims are better at high RPM with short term trims of ~ -4 to -5%. With this data the low RPM cruise short term trims are -20% and long term trims creep up to -10%.

I am wondering if this is bad injector data or did these changes mess with my speed density enough to require adjustments?

What are your thoughts? has anyone else made these changes to a 5.0 coyote and had to adjust speed densities?

I attached a log file for reference. rev05 tune long log.hpl

[Bill88stang]

What changes did you make to the speed density table? I like to see -3 to -5 on the stft, better to have it removing a little fuel then adding.can you post your tune file so we can see what you have done ?

[CCS86]

I don't believe that changing injectors would require any changes to the speed density tables. They are there to describe dynamic airflow/pressure. A straight fuel delivery change (a different commanded pulsewidth) won't affect that.

[CCS86]

Stuff I see:

• During steady cruise ~27 mph, your STFTs swing back and forth, giving a "rough" appearance. This means you should tune your O2 Transport Table
• Definitely log commanded EQ on one bank
• Log fuel flow as well, so you can calculate "fuel load"
• You are hitting WOT at 38% pedal. Definitely need some tuning of TQ tables / Driver Demand. This is helping to cause bad things, like reversion to stoich mixture at WOT (11:42)

All in all, the fueling doesn't look bad in this log. I think a slight decrease to injector offset, or increase to low injector slope, would get you there. It's hard to say which without logging a few more channels.

[dsandahl]

thanks. I will log those additional channels.

The base tune I am using is the FRPP power pack 2, from that I only changed the injector data and 2018 IMRC data.

I can upload that tonight along with new data.

[Bill88stang]

Yes please do so we can see what you have

[dsandahl]

I attached my tune and latest log file. fuel trims are looking better but still would like to dial in closer. Also look at the log around 6800rpm +. looks like the log indicates TPS% closing and then fuel starts backing down. I'm not sure if that is real data or if the data logging is getting interrupted or truncated for some reason. polling is at 20ms.

[Bill88stang]

I’ll check it out as soon as I get to my laptop and see what you have going on. How does it drive overall?

[dsandahl]

it drives good. I would like to refine my fuel trims and get input on what is going on in the data at 7Krpm +. thanks for the help.

[mstang_man]

This is good data from FRP47

fuel injector min pulse width 0.0006860
max allowed duty cycle 1.9900000
low slope 0.0143000
high slope 0.0130000
break point 0.0000130