Help Setting up over run fuel cut settings

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maych87
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Help Setting up over run fuel cut settings

Post by maych87 »

I just set up my engine state settings. They all seem to be working properly. I am now trying to set up my over run fuel cut settings. I am unsure what everything should be set to.

1. Should I be using ignition timing cut and why?

2.The highest and lowest rpm to re engage fuel. How do I figure this out or is there a standard recommended setting for each? Is there a reason you don't want over run fuel cut at high rpm? Why?

3. The rpm dot for upper and lower re engagement. How do I figure these out. Why are they not the same as the engine states. I used the recommended values for this setting will that be good enough

Attached is my tune msq. any help or modifications to my tune file would be greatly appreciated
Attachments
2017-11-27_11.45.59 set up over run fuel cut.msq
msq
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tryingbe
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Re: Help Setting up over run fuel cut settings

Post by tryingbe »

Manual or Auto?
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maych87
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Re: Help Setting up over run fuel cut settings

Post by maych87 »

Manual


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MegaMicra
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Re: Help Setting up over run fuel cut settings

Post by MegaMicra »

I haven't cut my ignition timing when overrun fuel cut kicks in as my original Nissan ecu didn't do that either and I'm trying to mimic most of what was oem.
I've tried cutting the ignition also but it made no difference to my setup. Mines not a high performance engine though. I can only assume Nissan leave it so the emissions are better; maybe to stop any unburnt fuel going through the cat.
I've set my rpmdot through trial and error coasting down hills. Probably not the right way but it's worked well for me.

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panel
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Re: Help Setting up over run fuel cut settings

Post by panel »

maych87 wrote: I am unsure what everything should be set to.
I'd try this first.....

RPM Greater Than (rpm)

Typically a number of hundred RPM above idle.

And MAP Lower Than (kPa)

Typically this will be below your idle kPa.

And TPS Lower Than (%)

This should be set close to zero such that over-run only enables when you really are off the throttle.

And CLT Higher Than (°F/°C)

Set this to prevent over-run operation on a cold engine.

After delay (s)

The delay prevents jerky on/off operation during transients
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enigmaticdream
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Re: Help Setting up over run fuel cut settings

Post by enigmaticdream »

Here are the over run settings I have on my 3.3l air cooled engine. I would suggest driving around tweaking the settings until you get what you like.
Attachments
over_run.PNG
over_run.PNG (38.47 KiB) Viewed 2224 times
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