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Open source tuning solution

aaronc7

Autocross Champion
Location
USA
Car(s)
17 S3
@joedubs made a quick informative video showcasing some of the features/operations of the open source tools as it sits today. Lots of recently dev and refinement on the Windows GUI/app. Not pretty but it works and does flashing and logging from the same interface. Not in the video, but to have a live data view during logging you would just open up Megalog and select the current log/csv being logged.:

 

aaronc7

Autocross Champion
Location
USA
Car(s)
17 S3
1620957084301.png
 

SuBNoiZe

New member
Location
Delaware
Been lurking here for a while & just found this thread while reading on the hptuners forum, who do I need to PM for the discord invite? I'm halfway decent with Linux and microcontrollers, coding from scratch not so much lol. Much respect for the work you all are doing to further the platform and really open it up to everyone
 

ShagginGSW

Go Kart Newbie
Location
MD
My goodness this is exciting. So using this opensource solution and whatever logger/interface/OBD2 port are you able to grab off the stock software from the ECU to save for reflash, should you ever need to? Is this strictly for the ECU or is there plans to do the TCU as well? If one is already tuned by a vendor can that tune be modified without completely wiping it out using this solution? I don't know how much use I would be but I like to dabble in this kind of stuff, if only just to learn a little more I would love to join the Discord.
 

joedubs

Go Kart Champion
My goodness this is exciting. So using this opensource solution and whatever logger/interface/OBD2 port are you able to grab off the stock software from the ECU to save for reflash, should you ever need to? Is this strictly for the ECU or is there plans to do the TCU as well? If one is already tuned by a vendor can that tune be modified without completely wiping it out using this solution? I don't know how much use I would be but I like to dabble in this kind of stuff, if only just to learn a little more I would love to join the Discord.
The ability to pull a file off the ecu via obd2 is completely disabled in code - so it only supports what's called "virtual read". Even commercial tools will read the box code from the ecu and then download the file from their own central repository.

You can flash over tuned files, depending on what key the file uses for the programming session. We obviously have the factory one and keys for some commercial tuners.

The way VW works, they have many different box codes which all use different software structures - so the maps are in different places. What we've done is consolidated around a software structure that's available on all the vehicles with Simos 18.1 (it's called s50). So golf sportwagen/alltrack, gti, a3, R, and S3 are all now running the same software.

We've got a pretty decent base file for the a3/gti (thanks @Exley ) that I'm running on my stock hardware a3, and a conservative stage 1 file that @J Peterman is running on his sportwagen. We've also got stage 3/MPI/Flex files (with flexfuel support for not just fuel but also ignition correction).

Tuning these cars isn't that difficult once you know where changes need to be made.

Finally, we can also recover ecus on a bench if you get hung up or there's what seems like an unrecoverable issue. We've only had to use it once and it's because @aaronc7 was probably drunk. He purposely flashed the wrong file. 😜

There's more details available at www.simoswiki.com for an overview of how things work. As far as actually flashing the files goes, you can do it with a windows laptop and a tactrix openport.

Edit: Yes theres plans to do TCU as well. Brian and I both did the majority of the development and coding, and up until recently, neither of us owned a DSG car. It's on my agenda though I'm not sure how far out it is. Hptuners is the best place to go for TCU RIGHT NOW if you wanna DIY.
 

ShagginGSW

Go Kart Newbie
Location
MD
The ability to pull a file off the ecu via obd2 is completely disabled in code - so it only supports what's called "virtual read". Even commercial tools will read the box code from the ecu and then download the file from their own central repository.

You can flash over tuned files, depending on what key the file uses for the programming session. We obviously have the factory one and keys for some commercial tuners.

The way VW works, they have many different box codes which all use different software structures - so the maps are in different places. What we've done is consolidated around a software structure that's available on all the vehicles with Simos 18.1 (it's called s50). So golf sportwagen/alltrack, gti, a3, R, and S3 are all now running the same software.

We've got a pretty decent base file for the a3/gti (thanks @Exley ) that I'm running on my stock hardware a3, and a conservative stage 1 file that @J Peterman is running on his sportwagen. We've also got stage 3/MPI/Flex files (with flexfuel support for not just fuel but also ignition correction).

Tuning these cars isn't that difficult once you know where changes need to be made.

Finally, we can also recover ecus on a bench if you get hung up or there's what seems like an unrecoverable issue. We've only had to use it once and it's because @aaronc7 was probably drunk. He purposely flashed the wrong file. 😜

There's more details available at www.simoswiki.com for an overview of how things work. As far as actually flashing the files goes, you can do it with a windows laptop and a tactrix openport.

Edit: Yes theres plans to do TCU as well. Brian and I both did the majority of the development and coding, and up until recently, neither of us owned a DSG car. It's on my agenda though I'm not sure how far out it is. Hptuners is the best place to go for TCU RIGHT NOW if you wanna DIY.

Can you explain virtual read, does it give the params but not allow them to be saved off or it just reads the box code? I assume if I am not currently running the consolidated box code and flashed it whilst being tuned by a vendor that would overwrite their tune.
 

The Dude

Autocross Champion
Location
PNW
Car(s)
MK7 GTI S
Can the flex fuel architecture and ignition correction be used in conjunction with any other tuning solutions? Like do a solid protune on say ecutek or cobb and then use this to basically activate and set scalars for ignition and fuel correction?
 

scrllock

Autocross Champion
Location
MI
Can you explain virtual read, does it give the params but not allow them to be saved off or it just reads the box code? I assume if I am not currently running the consolidated box code and flashed it whilst being tuned by a vendor that would overwrite their tune.
Reading the UM calibration is a little different. I'd avoid public discussion on that, they tend to be kinda retaliatory about people trying to dump their tuned ECUs. Best to join the discord (but yes, you'd be overwriting it).


Can the flex fuel architecture and ignition correction be used in conjunction with any other tuning solutions? Like do a solid protune on say ecutek or cobb and then use this to basically activate and set scalars for ignition and fuel correction?
Yes/no. You could use cobb to flash but I don't think you can edit someone's pro-tune without the necessary keys. You'd be surprised just how bad most pro-tunes are once you start looking at some of the calibrations out there, though.
 

ShagginGSW

Go Kart Newbie
Location
MD
Reading the UM calibration is a little different. I'd avoid public discussion on that, they tend to be kinda retaliatory about people trying to dump their tuned ECUs. Best to join the discord (but yes, you'd be overwriting it).



Yes/no. You could use cobb to flash but I don't think you can edit someone's pro-tune without the necessary keys. You'd be surprised just how bad most pro-tunes are once you start looking at some of the calibrations out there, though.
No one said UM, shhh.

Keys, are these tune files encrypted on the ECU or they require a key to allow you to edit them? Couldn't someone with a Cobb or other flash tool just grab the key?
 

aaronc7

Autocross Champion
Location
USA
Car(s)
17 S3
Flash data is compressed and encrypted.

He might be referring to the seed/key algorithm, aka tuner lock. Cobb does this so you can't flash over it with another tool whole the AP is still married to the car.
 

anotero

Autocross Champion
Location
Hither and thither
Car(s)
Mk7 GTI
@joedubs made a quick informative video showcasing some of the features/operations of the open source tools as it sits today. Lots of recently dev and refinement on the Windows GUI/app. Not pretty but it works and does flashing and logging from the same interface. Not in the video, but to have a live data view during logging you would just open up Megalog and select the current log/csv being logged.:

I see Python.
 

ShagginGSW

Go Kart Newbie
Location
MD
Flash data is compressed and encrypted.

He might be referring to the seed/key algorithm, aka tuner lock. Cobb does this so you can't flash over it with another tool whole the AP is still married to the car.
Does the ECU decrypt the data in real time or is it decrypted once the flash finishes? I'm asking because the best way I learn is from someone else's work, then I fiddle from that basic knowledge. So my questions about being able to read the current flash parameters is to get a baseline for what is acceptable and figure out why something was done. This platform sounds super cool and I think I would go this route once I decide to do IS38, MPI, E85, LPFP since I don't want to fork over a ton of cash for something I can feasibly do at home.
 
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