I totally understand. Usually Jake H. gives me a heads up with this stuff. He knows I want in. You guys can apply my Syvecs down payment towards any research and development, as well as the final product, for both boost box and flex fuel.
N54 Stock DME Flex Fuel
- Thread starter Jake@MHD
- Start date
I totally understand. Usually Jake H. gives me a heads up with this stuff. He knows I want in. You guys can apply my Syvecs down payment towards any research and development, as well as the final product, for both boost box and flex fuel.
I spent like an hour earlier debating whether or not I wanted to run e85 in my car considering the lack of stations around my state. I guess my mind is made up now haha
Incredible work to everyone involved, this is a game changer
Incredible work to everyone involved, this is a game changer
Now let's figure out how to control PI with stock DME
Hey guys,
The time has finally come to share some details on my secret N54 project. It's been under development for many months now, and had no shortage of both hardware and software (mainly software View attachment 1608) obstacles to overcome. That said, a major milestone was reached this week so it's time to let you all in! Coming soon to a stock DME near you:
View attachment 1604
Yep, real Flex Fuel. It is a fully implemented flex fuel solution, running on the stock DME! Dial your car in on pump (91-93oct), then E85, set the blending / interpolation curve tables, and be on your way. The benefits here are never having to reflash when changing ethanol blends again (or even worry about mixing the correct blend). Go from straight 93oct to 100% E85 or E98 on the same flash View attachment 1609
This is up and running on a few IJE0S cars now and works flawlessly. There is still some more work to be done, and of course porting to the other ROM types will take a good bit of time. Some hardware details are in need of finalization as well. More to come on those items in the weeks to follow.
Some overall highlights and features of this accomplishment:
- first DME integration with a 3rd party sensor
- first large scale rewrite and modification of DME logic
- direct logging of Ethanol Content % in MHD
- separate blending / interpolation per table grouping
- seamless blending between maps for any ethanol content
I'd also like to give a big thanks to @CKI for his help in testing and flashing my countless revisions at all hours of the day, and also to @Martial@MHD for assembly code and hex conversion help along the way! In case you haven't guessed, this will be a module available in MHD similar to M-Boost.
A thread is worthless without pics, right? This log was taken after a fill-up to a higher E content, and you can see the AFR target rising as E% goes up. 2017 is just getting started, and will definitely be the year of the stock DME
View attachment 1610
View attachment 1603
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Amazing job guys. I remember talking to you about this Jake. Just keep banging em!! Let me know if you need anything
If it's like everything else on the DME it interpolates so it should smooth it out a bit depending on the gap.
Looks like your axis breakpoints you set to the sensor output from 0-100% ethanol, and at whichever points you choose you can have an interpolation value from 0 (base map) to 100 (full e85 map). You can set 100% interpolation (full e85 map) at 70% ethanol, or scale it however you want non-linear or linear. The DME generally interpolates between values so it should be smooth.
Edit- other Justin beat me.
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There were rarely (if ever) be "hard break points" in a DME table axis. They most always have interpolation between values. You can also change the axis shown here to be whatever you want.
So between the points you set, the DME interpolates between those automatically so it's nice and smooth?
And these values just set points to shape the curve
Noice
The ethanol sensor itself should not matter as long as it is a genuine GM / Continental sensor that outputs 50-150Hz for 0 - 100% Ethanol. Some of the Chinese copies and knockoffs you see on EBay etc, for cheaper, are not calibrated correctly and will not be compatible.
The Ethanol Content Analyzer (ECA) is more specific though. This converts the Hz signal to a voltage range compatible with the DME. As of now, only our ECA has been tested and works with the DME for all voltage readings. I would suggest that users interested in flex fuel wait for the full release before purchasing anything, as the hardware and hardware kits will be released at the same time as the MHD module.
If one currently has the full replacement feed line with inline ethanol sensor, that is fine of course. They will just need the ECA + wiring harness, and MHD module of course.
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I would love for you guys to take my money for this!
Any idea on pricing? Release date?
Also, is this just a DME Flash or is this a "add-on"? Mainly curious due to the boost applications being dependent on octane.
Any idea on pricing? Release date?
Also, is this just a DME Flash or is this a "add-on"? Mainly curious due to the boost applications being dependent on octane.
This requires a hardware and software solution. The hardware is related to detecting ethanol content levels in the fuel system.
So, what would be the difference in running this versus fuel it's sensor + JB4/MHD
Their solution is not true flex fuel. It doesn't modify timing, afr, fuel scalar, iat compensation, etc etc.
