VS M4.4 tuning dead? Start again here?

[Chuck W]

I can't help you with why I can and you can't access the forums. Sorry.

I would like to see if I can extract any more info from that M4.4 tuning thread for archiving, though.

[rkam]

I'm also not able to access anything on Volvospeed.
I've tried different browsers, computers, phone, WinXp, Win10, Android..

[Josya]

Dear friends, Hi!
I have a question to ask you. I recently made several upgrades to my 850.

Firstly, I replaced the TCV (Turbo Control Valve), put it from V70. The same valve on the XC90, etc.

After that, I flashed this firmware, - 607_rev5c_test-tcvhack-850_tweak21.bin

In this firmware, I changed a few points on the turbo operation, in particular the overboost time "Time for the maximum boost pressure" (by default, it was 16 seconds, I set 8 seconds by experimentation).

I really like this firmware, the car goes much faster on it, the boost pressure is good, fast acceleration, etc. But there is a feeling that according to some parameters the motor (or automatic transmission) is running at the limit... I really try not to press the gas pedal all the way down , so as not to kill the engine. But! There are situations when you need to accelerate quickly, while when you press the gas pedal (throttle opening more than 80%), there is a kind of power failure, as if the ECU limits the torque or fuel supply. It feels like someone is holding the car by the ass... It may or may not happen. When this happens, it is unpleasant and creates difficulties with the traffic situation. Because the problem is unstable and a clear algorithm is not traced with its appearance, I think these are the settings of the software (because if I flash the standard firmware, there is no such problem). To the same point, I added that after reaching the revolutions above, therefore, a few questions: and sometimes a crackling can be heard (I can't say exactly where it comes from). This is similar to the crackling of an automatic transmission or some kind of cylinder (for example, hydraulic compensators do not cope) or, alternatively, the pressure in the intercooler is too high and the passing air flow creates an uneven space.

I have some ideas about how to solve this problem. Therefore, questions to experts:
1) Is it possible to configure the boost cards for a specific gear of automatic transmission?
2) Is it possible to change the automatic transmission gearshift speed programmatically?
3) is it possible to limit the engine speed to a certain automatic transmission gear?

I tried to find these settings on my own, but either I was looking badly, or I don't understand the correct algorithm of work, or (the saddest thing) there is no such possibility.

[xanthefin]

"automatic transmission gearshift speed programmatically".

I would wait like these happens in transmission module not in ECM. TCM sends example reduce torque signal to ECM but people who tuned M4.4 can flash more details what in ECM side as this was my quick take top of my head.. not in detailed one nor i can be specific in matter yet.

[Josya]

As I understand it, this post pursued the same goals as I did. But I thoughtfully read the algorithm several times and I also don't have a complete understanding of how to properly configure the turbo for the new one TCV.

https://m44.fandom.com/wiki/Tuning_load ... _Mechanism

[Josya]

Hello everyone!
Does anyone have an opinion on how the ECU works on different types of octane fuel?
Does the ECU understand the different octane number and is it possible to make adjustments for fuel with a lower octane number?
Maybe it is possible to introduce some kind of correction factor? Or somehow switch between fuel cards?

And another question. Does anyone have the knowledge whether it is possible to flash TCM (transmission control module)?

[Chuck W]

I know VAST has an option in his ECUs for an alternate mapset-

Alternate Mapset: A second map set, allowing you to switch injector calibrations, fuel map, ignition map and boost maps on the fly, without the need to flash a new tune. Usually this is used for a gasoline and E85 map, but can be used for water methanol injection or a high performance/high fuel economy map.

There is no way for the ECU to sense the fuel type/quality.

[Josya]

I know VAST has an option in his ECUs for an alternate mapset-

Alternate Mapset: A second map set, allowing you to switch injector calibrations, fuel map, ignition map and boost maps on the fly, without the need to flash a new tune. Usually this is used for a gasoline and E85 map, but can be used for water methanol injection or a high performance/high fuel economy map.

There is no way for the ECU to sense the fuel type/quality.

Thank You!

I was just trying to figure out if I could somehow try to adjust the fuel mixture in the ECU for better performance and economy. Because starting from 2200-2500 rpm, I have a detonation.

I think this is due to the low quality of fuel in Kazakhstan, the low actual octane number. The declared characteristics of gasoline do not seem to be observed in our country...

Dear Chuck, what is the octane number of your gasoline? It seems that low-octane gasoline is also used in the USA?

[Chuck W]

I'd have to dig back in the VS thread, but I think the base "DIY M4.4" stuff has the selectable maps, but I could be wrong.
I know there are alternative maps listed in the XDF. I don't remember how you select them though.

In run all of my turbo cars on the 93 PON octane. This is equivalent to 98 RON.

As far as your detonation goes, I haven't used that rev5c bin. All of mine started with the rev5b. I have tweaked VE, spark, and turbo maps and had some detonation due to a lean VE map (I was experimenting). I cleared that up with no issues. The car is now running a WBO2 modulation bin.

Sounds like you either need to dial back your turbo parameters or look more closely at your spark or VE maps.

[Josya]

I'd have to dig back in the VS thread, but I think the base "DIY M4.4" stuff has the selectable maps, but I could be wrong.
I know there are alternative maps listed in the XDF. I don't remember how you select them though.

In run all of my turbo cars on the 93 PON octane. This is equivalent to 98 RON.

As far as your detonation goes, I haven't used that rev5c bin. All of mine started with the rev5b. I have tweaked VE, spark, and turbo maps and had some detonation due to a lean VE map (I was experimenting). I cleared that up with no issues. The car is now running a WBO2 modulation bin.

Sounds like you either need to dial back your turbo parameters or look more closely at your spark or VE maps.

Dear Chuck can you please send screenshots of your settings?