Fuel Difference Map

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da40flyer
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Fuel Difference Map

Post by da40flyer » Thu Mar 28, 2013 1:48 pm

I have a "Fuel Difference" map grid in my cal file. It shows Load vs RPM with values as a %. It shows all zeros right now. What is this Map used for?

Thanks.

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RickS
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Re: Fuel Difference Map

Post by RickS » Thu Mar 28, 2013 3:26 pm

Assuming that the ECU that you have is an EM36, the Fuel Difference Map is employed when using primary and secondary fuel injection (triggered by option Fuel Diff Input) allowing two banks of injectors to be fitted to each inlet.

You will also notice an Ignition Difference that does similar for sparks.

RickS

da40flyer
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Re: Fuel Difference Map

Post by da40flyer » Thu Mar 28, 2013 9:22 pm

Thanks.

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RickS
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Re: Fuel Difference Map

Post by RickS » Tue Apr 02, 2013 8:03 am

You're welcome and if you need any more info, just ask. You can also download manuals from our website.
BR
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markcbz
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Re: Fuel Difference Map

Post by markcbz » Wed Apr 03, 2013 1:03 am

Fuel and ign difference on my em36 contribute towards the severity of my als strategy.

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RickS
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Re: Fuel Difference Map

Post by RickS » Wed Apr 03, 2013 7:57 am

Flexible isn't it!
Yes, this is an option but it was primarily designed for primary/secondary injection and then expanded to primary/secondary ignition. If using two sets of injectors arranged upper and lower banks where the upper bank is used for increased power at high rpm as you will know. The Fuel Difference table allows you to assign different percentage of the fuel pulse width to each bank.

The Fuel Difference table describes the percentage of the mapped pulse width at any given load and speed to be sent to the secondary injectors. The remaining pulsewidth will be sent to the primary injectors. eg if the map reads 20, then 20% of the pulse width will go to the secondary injectors, and 80% to the primary. This table is only used when the option Fuel Diff Input is satisfied. If this option is permanently required, the option can be always satisfied by setting it as 'Switch Always ON'. The values set in the twin injector options still apply when using the Fuel Diff table.

RickS

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