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sbeavenx sbeavenx is offline
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Join Date: Feb 2015
Location: Toronto, Canada
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Originally Posted by Reanimotion View Post
There is a firmware update available now on the downloads page of the website

FrankenCIS 5.4.4k - which addresses the issues mentioned for CIS-E applications
Hi Steve,

I've been bench testing the Firmware on my Microsquirt Module and everything seems to be working good. I now have a better understanding of the adjustment you made to "Cranking RPM" setting. Although the fuel is now supplied when cranking, it is using your Speed Density fuel formula rather the the 'Cranking Pulse %' settings.

What I understand is the MSExtra approach is to have two different fuel formulas, one for cranking and one for running. The formulas transition at the "Cranking RPM" setting, utilizing a the "Cranking Pulse %" calculation when RPM is below the setting, and the Speed Density fuel formula above the setting. This is why the documentation says to set Cranking RPM above actual cranking RPM by 200. This ensures the Cranking Pulse % calculation is used during cranking, but still low enough that Speed Density is used at idle.

The cranking pulse used with injectors in normally calculated by multiplying REQ_FUEL times the Cranking Pulse %, which is based on the coolant temperature. Although this approach would not work for your DPR mA calculation, REQ_FUEL could be set to 100 (0mA) and then multiplied by the Cranking Pulse % setting to arrive at the final value (ie. Cranking Pulse % = 140% --> 100*140 = 140 or +40mA). This would allow fine tuning cranking fuel independently of the Speed Density formula.

What do you think?

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Old 04-07-2015, 02:31 PM
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