Roland@pcmtec Posted September 5, 2018 Share Posted September 5, 2018 Update: This is obsolete in Falcons with a steering wheel as you can use the multi tune to select tunes/boost etc. This guide is only applicable for conversion cars without a factory steering wheel. To achieve dual maps in the flex fuel custom operating system you can wire a switch into the second o2 sensor input (pin A37). This will require a custom operating system with "dual maps" enabled and "user configured voltage selection". A great pinout is available here. 5v can be sourced from pin A36 http://www.thebarraguide.com/pcm-a-connector/ Here is the “Blend Ramp” for spark. By setting 0.6 volts to be 1.0 ratio it means once the voltage hits 1.1 volts it will use 100% of the other spark table. Once the voltage drops below 1.1 volts (eg switch off) it will go back to using the normal maps. The O2 Sensor input can read a maximum of 1.60 volts, anything above 1.6 will clip. 5v is the limit of the hardware, above this you may damage the input, eg do not wire 12 v into this input. auF100010 Any maps you wish to disable or not use, simply set the following blend curve ratios to entirely 0. This will mean the the PCM only uses the original maps under all circumstances. "Blend Ramp for Boost" auF100013 "Blend Ramp for Fuel" auF100012 "Blend Ramp for Spark" auF100011 "VCT Blend Ramp" auF100015 Finally you could also use a variable rotary dial to allow variable boost/power. This could be infinitely variable, or with various stages of boost. 1 Quote Link to comment Share on other sites More sharing options...
Loki Posted September 6, 2018 Share Posted September 6, 2018 How do you tune when you got your fuel tank mixed? Will the O2 sensor look after the tune? Eg. I have 4/10 of the tank filled with U98 then decided to top it up with E85 or vice versa. Will dual map give me clear advantage with tuning? And how? I am thinking about using custom OS hence this is my question ? Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted September 6, 2018 Author Share Posted September 6, 2018 32 minutes ago, Loki said: How do you tune when you got your fuel tank mixed? Will the O2 sensor look after the tune? Eg. I have 4/10 of the tank filled with U98 then decided to top it up with E85 or vice versa. Will dual map give me clear advantage with tuning? And how? I am thinking about using custom OS hence this is my question ? See the custom OS thread. It interpolates between the two based on the flex fuel sensor output. Eg E42.5 will be ~2.5volts hence 50% of 98 map + 50% of e85 map The advantage is you can fill up with 98 if you daily the car and aren't near an E85 pump, you also don't need to empty the tank completely when switching fuels. To do the full flex fuel tune you require a flex fuel sensor. Danny at Springy Performance sells a complete kit with fuel fittings and O2 sensor loom. Quote Link to comment Share on other sites More sharing options...
will15 Posted October 16, 2018 Share Posted October 16, 2018 (edited) I’m a bit lost, wire a switch into pin a37?. I thought we would wire the out put signal from the flex fuel sensor into a37. Edited October 16, 2018 by will15 Quote Link to comment Share on other sites More sharing options...
will15 Posted October 16, 2018 Share Posted October 16, 2018 My bad just read the custom os page, I get it now? Quote Link to comment Share on other sites More sharing options...
finnigan001 Posted October 29, 2018 Share Posted October 29, 2018 Hi Guys, Just on using the second o2 sensor for this and other inputs. Is the second o2 sensor used for anything useful other the detection of the cat failure? I used to think it did exhaust temp but that is just calculated by the ecu and also how would it do temp, ? ? hahahah, being an o2 sensor. Cheers, Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted October 29, 2018 Author Share Posted October 29, 2018 Correct it is used to check the efficiency of the catalytic converter. Commonly this check is already disabled as the user has modified the exhaust and catalytic converter meaning it no longer passes the efficiency tests. FYI Exhaust temperature is calculated by a lookup table of load vs rpm and then multiplied by engine coolant temperature exhaust flange temperature = (auF16613 base stead-state flange temperature * 200°F ) + auF1605 Exhaust temperature modifier for ECT * (ECT - 200°F) 2 Quote Link to comment Share on other sites More sharing options...
richardpalinkas Posted April 12, 2019 Share Posted April 12, 2019 when wiring in the switch into the circuit a37, is that to ground or to a 5v source? and if its to a 5v source, where are you getting the source voltage from? Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted April 13, 2019 Author Share Posted April 13, 2019 5v You should be able to find a 5v ref in the plug itself, I think it is used for the O2 heater. Make sure you don't use 12v as it may damage the analog input which clips at 1.66v in the BA/BF and 3.8v in the FG mk2 Quote Link to comment Share on other sites More sharing options...
richardpalinkas Posted April 15, 2019 Share Posted April 15, 2019 so do you need to put a resistor in place so that it does not go over 3.8v or is running up to 5v ok? Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted April 16, 2019 Author Share Posted April 16, 2019 5v should be fine and it just pegs the value at 1.66 or 3.8v from the testing we have done. If you have a resistor handy it can't hurt to use it though. Higher voltages may damage the input over time, I haven't been able to determine what the A/D limits are as it uses a separate chip on the PCM board and not the internal A/D converters that are used for the other 5v sensors. Quote Link to comment Share on other sites More sharing options...
80gus Posted March 6, 2021 Share Posted March 6, 2021 Why is this conversation Obsolete is there a different way to do this? Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted March 6, 2021 Author Share Posted March 6, 2021 6 hours ago, 80gus said: Why is this conversation Obsolete is there a different way to do this? Multi tune. You can wire up cruise control buttons and use a CANBarra module to power almost any dash to display the rpm signal from the PCM. No one we know of has used this method in over a year hence the obsolete status. Quote Link to comment Share on other sites More sharing options...
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