Hacking the Motronic ECU (Audi RS2)

[Dybro]

Sure. I even had to rewrite some bits of it...

For you, perhaps yes, since you lack the necessary skills. 8051 instruction set is tiny though...
That said, you don't need to disassemble anything to tune.

What are you trying to do?

OK. assume this is good news...

Maybe my plans are to extreme for a beginner. But anyway - here they are:

create multiple fuel- and ignition settings so that I can run it like a multifuel engine (gasoline ethanol, different blends of it. maybe also LPG/Autogas in the future).

Maybe I will use an ethanol-content-sensor(not sure yet - I could also choose to have a rotary switch to change map manually) actually 4 or 5 fuel- and ignition-settings + 4 or 5 cold start settings would be enough (15 in total)

a switch to select an other maf-sensor.

a switch to change the injector-constant-value

improve the throttle response(really think it's "lazy", and it is already chip-tuned)

Anti-lag system if possible

I also want to have motronic converted to wide-band-lambda if possible.


Can the trigger-logic in M2.3.2 be converted to 60-2 + cam-sync ? would be very nice in case of a flywheel configuration changes



If all this is to difficult and time consuming(sure it is time consuming) I might want to go for an after-market ecu. But not many after-market ecu's will support the 135-audi-trigger, and this is why I like the old Bosch.

[Jonas_R]

If you want all that you could just go with VEMS.

[prj]

create multiple fuel- and ignition settings so that I can run it like a multifuel engine (gasoline ethanol, different blends of it. maybe also LPG/Autogas in the future).

LPG/Autogas always has a separate ECU, which goes between the stock ECU and the injector outputs.
For Ethanol/Gasoline, it is possible to make a hardware switch.

Maybe I will use an ethanol-content-sensor(not sure yet - I could also choose to have a rotary switch to change map manually) actually 4 or 5 fuel- and ignition-settings + 4 or 5 cold start settings would be enough (15 in total)

Useless. One good setting is all that is needed.

a switch to select an other maf-sensor.

Useless, you will not fit different MAF's depending on your mood. Also, it took me two months to make a SW for a different MAF sensor.

a switch to change the injector-constant-value

Useless, if you change injectors, you remap. Or if it's E85/Gasoline setting, you just change setting via hardware switch.

improve the throttle response(really think it's "lazy", and it is already chip-tuned)

Boost is based on TPS value. And it is good that way, because it saves the turbo from unneeded stress.
If you want full boost, just press your foot down. There is a reason why the throttle isn't "on/off".

Anti-lag system if possible

Not possible.

I also want to have motronic converted to wide-band-lambda if possible.

Not possible. Use a wideband controller that has narrowband output. MAF is precise enough. Motronic does not need to run closed loop all the time.

Can the trigger-logic in M2.3.2 be converted to 60-2 + cam-sync ? would be very nice in case of a flywheel configuration changes

Not possible.

Buy an aftermarket ECU.

[Dybro]

Buy an aftermarket ECU.

Ok thank's.. then I will properly choose an after market ecu.. I have been playing around with the VEMS software, and unfortunately I don't like it.. I think all the settings are confusing(especially the triggering settings) Also I think that the map-switching possibilities don't satisfy my needs(I managed to find 2 settings only, a year ago I think). I would like 3 or 4 different settings.....

But I have found an ecu that should do all this. It is the adaptronic 1280s - 12 inj. 8 ign. and has almost all the fancy extra ecu functions plus PLC-like logic for custom functions. I really like the PLC-logic style.
Some people in a tuning shop in Holland is actually preparing the 1280 for common rail diesel. That's pretty cool IMO.

If some of you would like to check out the adaptronic 1280 software you can get it here http://adaptronic.com.au/files/e1280...3000_Setup.exe

If you want all that you could just go with VEMS.

Daw Jonas. Som du nok kan se, så er jeg ikke umiddelbart så begejstret for VEMS'en. Men da der er lavvande i kassen fordi jeg studerer, så kunne jeg måske godt fristes alligevel. Kan du hjælpe med opsætning af trigger + diverse på en standard AAN??? tror du det er nemt at sælge vems'en om 3-5 år(55-pin typen)?
På forhånd tak

[A80Avant]

why are you putting the turbo on uneccesary stress if you are asking for more boost on part throttle?

[Dan]

why are you putting the turbo on uneccesary stress if you are asking for more boost on part throttle?

I guess the argument would be that you're demanding more airflow, by asking for more boost, but then restricting that airflow with the throttle (increasing backpressure).

[prj]

Yep, pretty much.
You basically let the turbo spin hard all the time, building boost and then you strangle that boost (airflow) using the throttle plate.

That is why in proper electronic boost control the target boost table is a 3D table with throttle position taken into account.
This makes throttle response more adjustable and reduces unnecessary stress on the turbo, when you just want to accelerate slightly. Plus there is less backpressure during non-WOT operating conditions, which exceed spring boost, as the wastegate is open.

With our old external wastegates this is more limited, but with the newer internal ones, you can have a much wider modulation of boost pressure, thus further extending the life of the turbo.

[A80Avant]

well, that is true in one sence, but when you have the external wastegate and a stiff spring, you are trying to allow a big turbo to build up boost as fast as mechanically possible and therefore one of the ways to do that is to be able to allow for a fast TPS response as well.

On VEMS you have 2 separate tables, one for TPS vs Boost and one for the boost curve itself(simplest way to control boost), otherwise you can still have a 3d map of boost vs rpm as well.

I usually ask for 90% of rpm calculated boost when throttle is above 50% pressed, because on simple overtakes on low revs where the turbo is not kicking in due to lag, i want to be able to have a fast responce without having to go WOT all the time. Therefore on low revs, the turbo along with the N75valve is basicaly trying to keep the wastegate shut so that the turbo can build up the pressure fast. I dont think this is causing any more stress to the turbo itself. I understand that keeping 50% TPS and asking for 2bar of boost is more stresfull, but usually when the turbo is in the rpm range that it can give me that boost i do use WOT.

For me i think that having a more responsive TPSvsBoost allows for a more subjective and driver specific driving habit, and i do like it.On smaller turbos which spool faster it indeed may pose a bit more stress to it, it will surge more often, but i dont believe that it will extremelly alter the turbo's life

[Dybro]

by improving the throttle-response I mean tuning the tps-based transient fueling and not incising boost at part-throttle

[prj]

well, that is true in one sence, but when you have the external wastegate and a stiff spring, you are trying to allow a big turbo to build up boost as fast as mechanically possible and therefore one of the ways to do that is to be able to allow for a fast TPS response as well.

It is not "fast TPS response". It just kills any throttle modulation.
And your logic is very wrong. The bigger the hotside, the softer the wastegate spring needs to be.
The required strength of the wastegate spring is inversionally proportional to hotside size (proportional to backpressure).
Thus, a smaller turbo, with a smaller hotside requires a stiffer spring to drive to high boost levels, than to drive a turbo with a larger hotside to the same boost level.

On VEMS you have 2 separate tables, one for TPS vs Boost and one for the boost curve itself(simplest way to control boost), otherwise you can still have a 3d map of boost vs rpm as well.

Boost vs RPM is needed, because compressor maps are not flat. By having a boost vs RPM table you are able to make more torque/hp.

I usually ask for 90% of rpm calculated boost when throttle is above 50% pressed, because on simple overtakes on low revs where the turbo is not kicking in due to lag, i want to be able to have a fast responce without having to go WOT all the time.

And what for is your throttle pedal? Just make the pedal travel shorter.
I am sure you would like a device like "sprint booster" if your car had an electronic throttle pedal. Going WOT is perfectly fine and then slightly letting off when too much boost starts to build. Not to mention, that you will get faster spool/more power this way, then trying to spool when the intake is strangled by the throttle.

Therefore on low revs, the turbo along with the N75valve is basicaly trying to keep the wastegate shut so that the turbo can build up the pressure fast.

And increase the backpressure, and stress the turbo more than needed and reduce fuel economy. But I guess none of those things are important to you.

I dont think this is causing any more stress to the turbo itself. I understand that keeping 50% TPS and asking for 2bar of boost is more stresfull, but usually when the turbo is in the rpm range that it can give me that boost i do use WOT.

You are just wrong on this one.

For me i think that having a more responsive TPSvsBoost allows for a more subjective and driver specific driving habit, and i do like it.On smaller turbos which spool faster it indeed may pose a bit more stress to it, it will surge more often, but i dont believe that it will extremelly alter the turbo's life

If you use a stiff spring, you are already severely reducing the turbo's life. If you use a stiff spring and basically flat TPS mapping, you are doing it even more.

Remember, the TPS mapping comes into play when boost pressure exceeds spring pressure only.

[prj]

by improving the throttle-response I mean tuning the tps-based transient fueling and not incising boost at part-throttle

Transient fueling is very good on stock.
Fueling is not power. Spark is power, and fueling is only a tool to combat detonation.

This is really basics. Pick up a book.

[Dybro]

Transient fueling is very good on stock.
Fueling is not power. Spark is power.

This is really basics. Pick up a book.

Proper ign. timing is power - year sure.

Transient fueling is very good on stock - not in my AAN. Mostly it get to little fuel (a 1/3 second delay) if I step on it fast during idle or fast idle...

[prj]

Proper ign. timing is power - year sure.

Transient fueling is very good on stock - not in my AAN. Mostly it get to little fuel (a 1/3 second delay) if I step on it fast during idle or fast idle...

lol... idle...
And you have a datalogger with at least 1/3 second resolution as well? I would really like to see a log.

During *transients* fuel delivery is perfectly fine. There are no lean spikes.

[Dybro]

lol... idle...
And you have a datalogger with at least 1/3 second resolution as well? I would really like to see a log.

During *transients* fuel delivery is perfectly fine. There are no lean spikes.

Well.. it feels something like a 1/3 second. that's why I think the throttle-response is lazy. If I run it on E10 or E15 mix it get worse witch make me think that transient-fuel is to lean - even for pure gasoline..... (I don't have a wide-band probe yet)

But it has an unknown chip in it. Maybe the tuner didn't do his job properly.

[newsh]

So actually its not stock..