FreeFuel ECU patch - a flex fuel implementation to Evo ECU
#16
Newbie
Thread Starter
With ECA + GM sensor if you set sensor voltage 0.25V (equals to 5% ethanol) to to match 0% ethanol content and 4.25V (equals to 85% ethanol) to match 100% ethanol content then your gasoline maps will be for gasoline containing 5% ethanol and your ethanol maps will be for E85 containing 85% ethanol. I'm not sure how the ECU behaves if sensor output goes outside this range.
So it may work as is but I haven't disassembled that ROM so I don't know.
The GM Flex Fuel sensor outputs a frequency signal for content (50-150hz, 0-100% content). It would be VERY cool if this could be run into the ECU directly to avoid having to buy the Zeitronix unit. The only frequency-based ECU input I can think of would be the Vehicle Speed input (or MAF freq if running speed density). This might take some pretty hardcore code but think of how great it would be if we could read the sensor’s frequency output directly. If not, I’m sure one could make a cheap digital to analogue converter module.
You could make cheap analog converter with LM2914. I experimented with that earlier but it was not as accurate or linear as the microcontroller solution I have now.
Sensor itself is very fast and power on delay is not significant. So it depends on the frequency-to-voltage converter. The converter I use has some signal filtering but still if I have been using gasoline and fill up with E85, engine runs perfectly from the start. It takes few seconds until the new mixture gets to the fuel rail but you really can't hear or feel the change at all.
Unfortunately I have nothing to do with development of the converter that I use so I can't give any details about it.
#17
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Sensor itself is very fast and power on delay is not significant. So it depends on the frequency-to-voltage converter. The converter I use has some signal filtering but still if I have been using gasoline and fill up with E85, engine runs perfectly from the start. It takes few seconds until the new mixture gets to the fuel rail but you really can't hear or feel the change at all.
Unfortunately I have nothing to do with development of the converter that I use so I can't give any details about it.
Unfortunately I have nothing to do with development of the converter that I use so I can't give any details about it.
Aaron
#19
Newbie
Thread Starter
It looks that GM is again using sensor in it's newest Flex Fuel vehicles instead of software solution. Sensor part numbers seem to be 13577379 and 13577394. I found one reference with google which suggests that the output could be the same 50 Hz - 150 Hz as the older sensor.
Why is this interesting? These sensors are 66 USD online...
Unfortunately this is all I know at the moment. Hopefully someone can give more information about these new sensors.
Why is this interesting? These sensors are 66 USD online...
Unfortunately this is all I know at the moment. Hopefully someone can give more information about these new sensors.
#20
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It looks that GM is again using sensor in it's newest Flex Fuel vehicles instead of software solution. Sensor part numbers seem to be 13577379 and 13577394. I found one reference with google which suggests that the output could be the same 50 Hz - 150 Hz as the older sensor.
Why is this interesting? These sensors are 66 USD online...
Unfortunately this is all I know at the moment. Hopefully someone can give more information about these new sensors.
Why is this interesting? These sensors are 66 USD online...
Unfortunately this is all I know at the moment. Hopefully someone can give more information about these new sensors.
-Bink
#24
Newbie
Thread Starter
Not at the moment.
I haven't done much research but it seems that Evo IX doesn't have a single ROM that could be used in US and EUR without issues.
So it would need to be ported to 88580714 and 88590715. I will probably do that some day but for the next month or so I'm going to be extremely busy so it's not going to happen overnight unless somebody else wants to do it.
I haven't done much research but it seems that Evo IX doesn't have a single ROM that could be used in US and EUR without issues.
So it would need to be ported to 88580714 and 88590715. I will probably do that some day but for the next month or so I'm going to be extremely busy so it's not going to happen overnight unless somebody else wants to do it.
#25
EvoM Guru
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Not at the moment.
I haven't done much research but it seems that Evo IX doesn't have a single ROM that could be used in US and EUR without issues.
So it would need to be ported to 88580714 and 88590715. I will probably do that some day but for the next month or so I'm going to be extremely busy so it's not going to happen overnight unless somebody else wants to do it.
I haven't done much research but it seems that Evo IX doesn't have a single ROM that could be used in US and EUR without issues.
So it would need to be ported to 88580714 and 88590715. I will probably do that some day but for the next month or so I'm going to be extremely busy so it's not going to happen overnight unless somebody else wants to do it.
I dont use livemap though because I dont have a cable for that yet, but I do have an op 2.0 currently. Im trying to pick one up second hand!
as long as this code wont disable any of the SAS function Im ok.
Last edited by 211Ratsbud; Nov 3, 2012 at 06:07 PM.
#27
Been following this and the other flex fuel thread mrfred and then donner were contributing to. Very interested in a 88590715 ROM even w/o boost interpolation since I'm on stock turbo and intercooler anyways.
Been getting cabin fever this winter and need a project like this. I hope this is still being worked on and thanks for your contributions in advance.
Been getting cabin fever this winter and need a project like this. I hope this is still being worked on and thanks for your contributions in advance.
#28
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Okay, I gotta ask especially now that there seem to be guys who have finally really gotten down SD and now we're delving in Flex fuel. Maybe this needs to go in another thread, and if so, please direct me to it.
Is anyone on SD also running the flex fuel and making big power (650+ whp)? If so, how is the drivability? Have there been any issues with tuning and scalibility of injectors and such, especially when running say a 2000cc injector? Also, any weird glitches or hiccups s far?
The reason I ask is because now that this is finally a reality, and now that there are tuners out there who have mastered speed density on the stock ecu, I'm considering making the switch back from standalone.
Is anyone on SD also running the flex fuel and making big power (650+ whp)? If so, how is the drivability? Have there been any issues with tuning and scalibility of injectors and such, especially when running say a 2000cc injector? Also, any weird glitches or hiccups s far?
The reason I ask is because now that this is finally a reality, and now that there are tuners out there who have mastered speed density on the stock ecu, I'm considering making the switch back from standalone.
#29
Newbie
Thread Starter
It has been quiet in my front. but I hope to find some time to research what would be needed for Evo 9 ROM port and boost interpolation. I do have already some Evo 9 ROMs disassembled but I don't have any commented disassembly from some other developer so it will take some time to understand the differences to Evo 8 ROM. It would be also good to find a test car as I don't have anybody locally with Evo 9 who would be interested.
My car is running MAP EF2 and 1100cc FIC inejctors. No problems tuning with those.
My car is running MAP EF2 and 1100cc FIC inejctors. No problems tuning with those.
#30
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It has been quiet in my front. but I hope to find some time to research what would be needed for Evo 9 ROM port and boost interpolation. I do have already some Evo 9 ROMs disassembled but I don't have any commented disassembly from some other developer so it will take some time to understand the differences to Evo 8 ROM. It would be also good to find a test car as I don't have anybody locally with Evo 9 who would be interested.
My car is running MAP EF2 and 1100cc FIC inejctors. No problems tuning with those.
My car is running MAP EF2 and 1100cc FIC inejctors. No problems tuning with those.
However, in times past in the infancy of new roms there have been unexpected "hiccups" that have had to be worked out. Thus, my curiosity if any has yet to run in to any running a comparable or larger setup. I REALLY want to do this. I just don't want to be a guinea pig in the large HP territory.