Kika

The first thing I learned from this thread is that there are a whole lot of Rennlisters that understand these cars WAAY more than I do.


Actually I knew that a long time ago, but this thread certianly confirms it.


And that is one of the primary reasons I subscribe to Rennlist.

evoderby

In reference to the most recent posts, here's an interesting post by Neel on programming anti knock using Pectel EMS.

https://rennlist.com/forums/9064625-post54.html

It indeed shows strategies used to distinguish knock from regular engine noise, it also shows the potential to generate additional power.

Juha G

Yes! We have a functioning ECU with MAP sensor!!

We ended up installing the MAP sensor on the ECU due to couple of reasons. First a MAP sensor that can be fitted in the engine bay costs about 150euros whereas a circuit board installed sensor is only 1/10th of the price.
Secondly the feed voltage for the MAF sensor is 12V whereas the MAP is usually 5volts. Allthough there definately are MAP sensors available for use in 12V circuit.
When the sensor is installed on the ECU, you need to run a vacuum hose from the intake into the ECU. That's about the only downside.
The good thing is that this way the ECU can use both MAP and MAF. We haven't tried using MAF based operation but the possibility is there. Using MAF makes this 100% plug and play.
Using MAP is 99% plug n play as you need to run the vacuum hose. But that's not very difficult.

Next week the proto will be sent to Mike (Stealth). He has experience with the older MS systems so he is the perfect guy to test it.

Next up he will start working on the 55-pin proto...

MAP sensor installed on the ECU:


Vacuum hose installed on the intake:

evoderby

Juha, VERY nicely done.....congrats!!!

Kika

and as a point of reference, my big accomplishment for the weekend is taking my daughters to the library to renew their passports.

Nice work Juha, keep us posted

Juha G

Thanks guys, but the honors should really go to my friend who is the mastermind behind this. I'm just merely helping by providing him a test platform (my 993) and taking part in the troubleshooting etc.

I'm also very happy that the proto is finished as now I can start tearing into the engine bay for the supercharger install. Something I've been anxiously waiting for for the past couple of weeks..

Lorenfb

"Yes, it is not simple but my point was that it is possible and the situation is same as with any other aftermarket ECU."

The issue is to properly and fully characterize the knock signal, i.e. since each engine has a different
knock signature. It requires a rigorous waveform analysis in the time domain and not like a relatively
simple task as tuning an engine or even interfacing an EMS to a 911 engine. Using a generic knock
control system will never provide the required capabilities necessary to achieve maximum torque
while avoiding detonation. Each engine requires a unique knock algorithm.

Geoffrey

You might think about sending your MAF to a company that can provide the airflow / voltage calibration. Once you get that, you can provide the ECU with the MAF sensor calibration table and then use the MAF sensor for load. This will work provided the camshafts are not too agressive with intake pulsations.

JasonAndreas

The motronic in the 964 and MY95 993 uses the CHT only during the startup phase(s). The 8-bit A/D hits 255 pretty quickly (300F or so, maybe less, its been a while since I've played with this) and at that point all the compensation maps (see below) are ramped to zero.

Acceleration Enrichment Clamp by CHT
Additional fuel for idle warmup
Additional fuel for part-throttle warmup
Additional Fuel During Cranking by Temp
Post-start additional fuel
Overrun RPM Turn On
Cranking Timing Correction by CHT
Tiptronic in Neutral Timing Trim by CHT
Ignition Trim BOOLEAN for heating catalytic converter
ISV Setup (Initial Value)
ISV Startup CHT Compensation
Tiptronic in Gear
Injector Constant (Not a really a constant)
Injector Compensation During Startup

mk1gt500

Hi I have a 993 94 tip that i want to change to manual will this ecu allow for this conversion


Regards


Josh

Juha G

With regards to the knock control, I think there is no need to continue the discussion in this topic as it is somewhat irrelevant.
If you want to keep knock control, easiest is to stay OEM. If you go aftermarket you will not have it unless you buy a knock control unit and teach it to read knock signals. Same applies to this ECU. So this ECU is no different from any other aftermarket ECU when it comes to knock control. It is certainly possible though.

I would think the calibration values for the OEM MAF sensor are available somewhere!?
If not, then I suppose it is easiest to use the MAP sensor.

Ok, that's good to know. Thanks!
I looked at the Motec file and there ignition was retarded when CHT reached 220-dgr C.


Hi Josh!
Yes, the 55-pin version would definately work on a manual car. Tiptronics we haven't even thought about yet...


Stealth seemed interested in giving the proto a try but I haven't heard back from him yet. If it turns out he is not interested after all, then someone else with a 96-97 needs to step up on the plate.

Eric_Oz_S2

Yes - you would need to do it yourself. BUT, this is also true of non-standard standalone ECUs. Most tuners are only familiar with certain ECUs (Motronic, Wolf, etc) and would not be totally comfortable with an unknown system. TunerPro does require the user to determine the definition file, but in reality this isn't hard if you only need to adjust basic fuel and ignition timing systems. It is when significant changes are made (eg high boost) that the Motronic tends to fall short.

Removing the EPROM is a simple task, and is replaced by a plug connected to the emulator which has it's own "electrically" rewritable EPROM that can be changed live while the engine is running. It also has the ability to trace what cell in a map is being accessed.

Some ECUs allow self programming - ie you set some parameters and the ECU programs in the gaps. ie set target lambda (closed loop) and it will adjust the injector pulse until the correct AFR is achieved.

Is your system self learning - ie is there a feedback through the WBO2 back into the map programming?

Sounds like an interesting project though.

Juha G

Hi Eric,

The basic idea of this ECU was to have a true 100% plug and play (no adaptors, no need to touch original harness or sensors etc.)
and with easy user interface.
I think we have been able to achieve that.

While using the emulator is surely an option, it is far from plug and play in my opinion. You say it is easy to remove the eprom from the board and replace with the plug. But how many are ready to fiddle with the original ECU?

While it is true that both methods require the tuner to learn using the software, I am under the impression that this emulation route is not very simple.
On our ECU the software is very logical and if you can tune Motec, you will learn to tune with this in no time. Principles are same and, it is just different key strokes and menu windows.

It is really two different approaches in my opinion. I'm not saying that your method would be no good but I am quite sure our method is much much simpler and easier.

MarinS4

Excellent job Juha!

There are outstanding low cost stand alone ECU's for other marques. Why not the Porsche? I installed a Mega Squirt PNP2 system for Miata last week. Feature rich and lots of tuning resolution. All for $800 USD.

I am very close to installing the Link G4 Extreme in my 993. When I compared it to various Motec ECU's I found it to have more of the features I wanted at half the price.

With all of the great stand alone ECU's available why would you build your own? I would think a adapter harness for one of the mass produced ones would have made more sense.

I would love to hear more about your system.

Juha G

Thanks for the compliments but they should really go to my friend who is behind this ECU.

When you ask why, the answer is easy; it's a nice hobby.

While there are several cheap ECUs that can be made plug and play with a adaptor harness, there none that do not require an additional harness.
This ECU just plugs in and you are good to go.

We haven't sent the proto out to Steve yet because my friend decided that he wants to have some one closer to test it. Let's see how it goes. I think we may have some news in the next couple of weeks.
He is also working on the 55-pin version.