Help Me Understand These Power Fc Settings...

[SargeRX8]

I took this screenshot from the current tune in my car. After reading some online sources about power fc tuning, I recalled these settings and from what I have read, they should not have been changed. From what I know, these settings are used to alter the AFM calibration if it has been housed in a different sized tube to what it comes with standard. My car is running in the standard afm housing with 3" piping infront and to the turbo. According to what I have read, these settings should not have been changed. When I got this tuned the second time(the current tune), we didn't think to check this tab and it was only weeks after we had noticed it. Now its been a year later and I'm looking to try do some DIY tuning to help increase the fuel economy on my car and just eliminate some knock in the upper end.

If I changed this back to default; 100 all the way down, will it throw out the tune, mainly the injector map? My car is a standard motor with the SS2 turbo and supporting mods with the Z32 AFM.

Thanks all.

[urtwhistle]

Yes it will alter your tune. Your fuel map references the airflow values vs load and that's how it knows how much fuel to throw in.

If u have a wide band setup it's very easy to see how changing those values affects ur tune. Ie ur fuel map may say 14.7 afr reality is that it's 14.2 so u tune the corresponding afm voltage up or down till the fuel map matches reality.

[SargeRX8]

Isn't what you said about altering the afm voltage about altering the air flow curve table? The air flow curve table lets you see the load point then alter the air flow voltage at that point. The part I'm picking on is the top part where you select the AFM you want and the numbers next to it. Everything Ive read said to leave those at default 100 when using the chosen AFM in the standard diameter housing.

[Dose Pipe Sutututu]

it's because some tuners bend the AFM scaling to tune the car rather than set the injection table... not sure if it comes to preference or sheer laziness, I've always had mine all default and adjusted the injection table to suit (back in the days when I did road tuning for myself)

[Guilt-Toy]

are you having issues with the way the air flow curve goes down the map during a power run ? or cruising?

if everything is working fine then just leave it and fix the issues you have.

or re-set the pfc and start again. i used to play with the air flow curves, but i had a q45 afm and major reversion issues.

[SargeRX8]

Issues are with cruising. My wideband shows a pretty rich mix 12 to 13 cruising.. If I did want to start again would I be safe to use the current ignition table? Really have no problem with power its just the way it skulls down fuel and I am a pretty calm low rpm driver. Haven't had a chance to do any logging yet to see what's going on with air flow curves and load.

[scotty nm35]

Get the o2 feedback working again.

[SargeRX8]

Does that mean I need to move my wideband? Its sitting in the standard o2 sensor bung. Is there a way to use the wideband for o2 feedback?

[GTSBoy]

Widebands usually offer a narrowband simulation output.

[scotty nm35]

Or simply weld another bung in?

Which wideband are you using?

[SargeRX8]

Aem. Just checked. Doesn't do simulation. I'll get another bung in.

[scotty nm35]

AEM has a set narrowband output, just no adjustment.

[Dose Pipe Sutututu]

^ I don't remember the AEM UEGO having a narrow band? I know Innovate LC-1 has it

[scotty nm35]

Sorry, I just checked and they only have the 5v output it seems. You can possibly find a circuit to drop it to 0-1v narrow band simulation...

[SargeRX8]

It wouldn't be hard to drop the voltage but I think its more thsn just dropping it. I'd suspect it has to be scaled to 0 to 1v. Ive got a bung at home and should have my o2 sensor which is almost brand new so I'll try get it mated up. If fuel eco doesn't change much ill try do some leaning to the cruise charts. Ill upload a screenshot of the table ive worked on so far.

[scotty nm35]

http://www.schnitzracing.com/manuals/AEMWBK.pdf

Page 9 of the manual states that P4 on the rotary switch is 0-1V output. I thought it had narrowband simulation built in... Try it out...

[Dose Pipe Sutututu]

anyways I suggest you turn off O2 feedback on the PowerFC and tune the A/F so it's stoich on cruise and light throttle.. once that's all set up just plug up the stock O2 and see if it still reaches stoich.. if not it's time for a new stock O2

[sydking]

are you having issues with the way the air flow curve goes down the map during a power run ? or cruising?

if everything is working fine then just leave it and fix the issues you have.

or re-set the pfc and start again. i used to play with the air flow curves, but i had a q45 afm and major reversion issues.

How did you sort reversion issues? My air filters sound like Darth Vadar the way they breath in and out

[SargeRX8]

I haven't loaded this tune yet, I'm going off current actual afr's and looked at another tune I found of a car with similar mods. I didn't make significant changes but what I tried to do was get everything flowing smoothly and evenly.

I'll need to do some more logging see what cells are being hit the most during common, light use and work with those but overall I think if it blends in more evenly and consistantly, it should run smoother and there won't be such drastic changes in afr's when cruising.

[Guilt-Toy]

Issues are with cruising. My wideband shows a pretty rich mix 12 to 13 cruising.. If I did want to start again would I be safe to use the current ignition table? Really have no problem with power its just the way it skulls down fuel and I am a pretty calm low rpm driver. Haven't had a chance to do any logging yet to see what's going on with air flow curves and load.

well stop looking soo much into it and just adjust the areas of the map that need weaking and lean it off. leave everything else the way it is. why touch something thats not broke ?