Tuning For Maximum Economy, And Leanest Safe Afr

[paulr33]

has your airflow correction been adjusted?

[paulr33]

my airflow table

[Cubes]

Airflow is all 100%.

With the R33 Airflow correction table it wouldn't idle, unsure why as its running everything R33, being the airflow curve, maps, etc..

With regards to afm voltage, it peaks at 4330mv, being 4.33v.

Running the std afm that would be around 5 to 5.1v.

[paulr33]

nice nice

i got no idea why mine is 166%

[Cubes]

When u init the pfc does it set the values within the pfc to 166% also?

I was thinking it may have been a datalogit supplied basemap thing.. no idea really.

[Cubes]

I've attached a tuned vs untuned compare map.

The red indicates leaned off.

For example if the initial value is 1.000 the modified value is 0.996 the compare map will indicate a red value of 4. Derived from 1.000 - 0.996 = 0.004.

unsure what the +19 value is at load point 9 rpm N06. Possibly a tuning slip up.

An hour was only spent working on light load so it isn't a perect tune, the other hour was trouble shooting.

The tunes rough enough for now. No point spending big $$ (500-600) on a nice tune when there's bigger turbo's to come and will most likely require a map resolution (map reference) change.

[GTRNUR]

Well I went for a long drive today. Did 230km's and used 1/2 a tank of fuel. Now I was driving normally for about 80% of the drive, I did some overtaking and saw 160-170k a few times... and the first 1/6 of the drive was actually a hill climb up a local range where I just couldn't help myself playing chase with someone in an evo 4 and occasionally hit around 5500 rpm at 16lb. Incidently this is about 10-11ms pulse width on the injectors. I also sat on about 120k's for 3/4 of the trip home.

Relivent details for the engine are.... RB20DET 100% internall stock, GT25 BB 400, 0.64 compressor, 0.7 turbine, Wolf ecu, front mount IC. My GTS4 has a manual gtr gearbox too, not the auto.

Here's my current map settings approx...As a lot of you use MAF instead if MAP sensors i'll translate to PSI and you can all work it out from that...

Below 2000 RPM...

0 PSI - 14.2

-5 in-hg - 14.0

-10in-gh - 13.8:1 (going slightly rich here really helped make the throttle response snappy.

-18in-hg 14.2 to 13.8 depending if aircon is on at idle, and about 14.0 when cruising.

Above 2000 RPM

2psi - 14.2:1

0psi - 14.7:1

-5in-hg - 15:1

-10in-gh - 15.5:1

-15in-hg - 16:1

-20in-hg - 0:1 (0ms fuel value)

Ignition advance was at 36 degrees. at 0 psi and increases to a max of 38 or 42 under vacuum. I can't remember exactly how far it advances.

I am also using decceleration En-leanment. The reverse of a throttle pump setting to lean things during negative throttle movements, which is one of the advances settings for economy tuning the wolf.

Closed loop operation was disabled for the whole drive.

The resutls... All in 5th gear.

Peak cruise power was found to be at about -5hg on the boost gauge at 100-105k's in 5th gear on level ground. The injector pulse width maxed out at about 2.40ms to 2.45ms. This was while at a 15.5:1 AFR.

Increasing speed to 110k's increased the fuel requirement to about 2.6ms and the resulting change to 14.7:1 AFR at 0 PSI.

Finally at 120k's the fuel requirement increased further to 2.8ms and again maintained around 14.7:1 AFR at 0 PSI.

So, I think with this tune if I were able to keep my right foot under control (or install a throttle stop) I could possibly see 500k's with this tune.

I'll post the actual map up tomorrow.

I'll have to also see how things go this next week with driving around town economy. Results will be posted.

Cheers,

Ian

[Cubes]

GTS4Newbie,

You say deceleration derichment or what ever it is.

Do you mean deceleration fuel cut or ?!?

Thanks for sharing your setup.

I really need to get my hands on a wideband for a few days.

[GTRNUR]

Well the wolf uses a setting called Transient Delcel Enleanment. It does the reverse of a throttle pump and reduces fuel delivered to the engine during deceleration.

Eg... SUppose you are cruising at 100k's and start to go down a slight incline, you remove your foot slightly from the accelerator to maintain the same road speed. The wolf will reduce fuel delivery a pre-set amount for a preset limit, exactly the same as a carburators throttle pump would add fuel during acceleration, but reverse. This keeps reduces un-necessary overfueling while the ecu settles on a new RPM/MAP sensor position on the fuel map.

Remember the reason for transient enrichment in a carburator is to deliver extra fuel to stop hesitation during sudden throttle position changes, while map or maf sensors settle on a new load setting. Transient ENLEANMENT does the opposite to concerve fuel.

I also use Over run fuel cut, which is meant for when your rolling down a hill and take your foot off the accelerator. Above 1600 RPM and at 0 throttle the ecu stops all fuel delivery and lets the engine naturally reduce engine speed. Its also used between gear shifts.

You turn both these off if you want to maintain boost better between gear shifts and are racing or something.

Hope that helps...

Cheers,

Ian.