NefMoto

I know there are several threads about specific injectors and their specs and general advice around KRKTE, TVUB, FKKVS. However, I'd like to start a thread that was for logging and fine tuning injectors that you might not have the specs for and could be used for fine tuning injector that don't seem to behave correct when their specs are used.

I'd like to discuss what to log, how to look at the data, and how to interpret the data then apply changes needed gathered for data.

Start with a estimated KRKTE - > KRKTE Cheat - Dial in those injectors faster! (http://nefariousmotorsports.com/forum/index.php?topic=2625.0title=)

Turn off multiplicative and additive adaptive correction -> set NOLRA 0 and 1 bits = 1

the log rl_w, ti, rpm, frm_w (or fr_w?), mshfm_w, uhfm_w

This is how I look at data:
02 reg vs ti
(http://creativeion.com/rey/vw/032e_02reg_vs_ti.gif)

02 reg vs rpm
(http://creativeion.com/rey/vw/032e_02reg_vs_rpm.gif)

then view avg by FKKVS nodes
(http://creativeion.com/rey/vw/032e_avg_02reg_rpm_ti.gif)


There's where my knowledge/experience ends. So how else should we log, then look at data? And then how should we interpret data (start with example above) to extract changes we need to make?

Thanks,
Rey

I just realized this probably applies more to wideband guys that narrowband. Sorry.

I think it is more likely you are looking at MAF non-linearity than injector non-linearity.

Injector limitations simply do not look like that... they're generally simple latency issues, which would be much easier to spot in your scatter plots.

Do a similar heat plot of MAF/RPM vs fueling error...

Ah OK. So need to add  mshfm_w and uhfm_w  to values to log.

02 Reg vs maf mass flow
(http://creativeion.com/rey/vw/032e_02reg_vs_maf_mass.gif)

02 Reg vs maf v
(http://creativeion.com/rey/vw/032e_02reg_vs_maf_v.gif)

Maf mass flow vs v
zoom in on high reg area
(http://creativeion.com/rey/vw/032e_maf_mass_vs_v.gif)

Maf v vs mass flow
zoom in on high reg area
(http://creativeion.com/rey/vw/032e_maf_v_vs_mass.gif)


I don't see anything weird, but that's not saying much.

one more

ti vs maf mass flow
(http://creativeion.com/rey/vw/032e_ti_vs_maf_mass.gif)

This one looks like it might shed some light.

Yea, can you plot a heatmap again?

MAF, RPM, error..

Hell, you can feed the results back into KFKHFM...

How are you coming to the conclusion that it's a MAF calibration issue vs an injector calibration issue?

I'd like to discuss HOW to read the data to come to said conclusions.

Thanks,
Rey

O2 Reg vs maf mass flow and rpm
(http://creativeion.com/rey/vw/032e_o2reg_vs_rpm_mass.gif)


O2 Reg vs rl and rpm
(http://creativeion.com/rey/vw/032e_o2reg_vs_rpm_rl.gif)

Because there is absolutely no reason for injector "error" to come from anything except latency and bus voltage (both of which can be corrected trivially via TVUB) if you have a proper fuel pump and FPR, whereas there are a zillion different reasons why a MAF might read differently depending on current operating conditions, in particular, certain flow/rpm regions.

Lets put it this way. Stock FKKVS is flat. Stock KFKHFM is... well... not so flat.

Injectors and fuel systems are very simple animals and are trivial to model with very simple equations.

MAF and intake setups... not so much.

What software are you using to plot the heat map?

old excel 2000 + pivot and surface chart. Need to create extra columns that round your axis values first. i.e.
round rpm to the closest 100 or 200 and round maf values to closest 2gs/s. Then create a pivot table with rpm and maf as rows and column and then o2 reg as data (average).

Ok, I did wonder how you were getting all the data in Excel but i see you are rounding which is fine i guess.  I might try and do a 3d scatter with Matlab.

Rick

For the first heat map where I displayed reg on FKKVS nodes (map) I did a lookup on rpm and ti and found which node it would fall on, then used that node value as axis in pivot, still rounding to closest node.

What injectors are you using? Are you on a returnless system?

I believe the low PW non-linearity should be concidered if using big enough injectors, IIRC I have compensated over 10% at some of the lowest pulsewidths.