MSD81 Variable redline

[superwofy]

I always found the variable redline on the M3 cluster to be somewhat useless as it fully disappears way before the engine is warmed up. The best I managed to do before was simply to increase the starting steps with the PerfektToolbox.

I was going to start controlling it with the CAN device but realized that there are tables that control the breakpoints in the IKM0S winols file. Offsets were wrong but I corrected them. I created a tunerpro XDF that has everything. Enjoy!

These values will depend on how your cluster is calibrated and what the starting position set with PerfektToolbox is.

 

[RSL]

I always thought that was done in Kombi coding/programming, pretty cool find. You have orange and red revs at the same address. ip_n_max_2__tco is at 4B1F4. Maybe it only pays attention to orange, just pointing it out.

 

[superwofy]

I always thought that was done in Kombi coding/programming, pretty cool find. You have orange and red revs at the same address. ip_n_max_2__tco is at 4B1F4. Maybe it only pays attention to orange, just pointing it out.

Yeah, I forgot to change the offset when copying the table. Fixed now in the first post.

What you can do through the KOMBI EEPROM is adjust the motor steps for a given RPM value.

The RPM values are sent by the DME in CAN message 0x332. It's composed of two bytes, one "orange" and one "red" and is sent every second.

13:00:29.334 -> 332:  0x5E 0x81
13:00:30.351 -> 332:  0x5E 0x81
13:00:31.335 -> 332:  0x5F 0x81
13:00:32.351 -> 332:  0x5F 0x81
13:00:33.368 -> 332:  0x5F 0x81
13:00:34.352 -> 332:  0x5F 0x81
13:00:35.336 -> 332:  0x5F 0x81
13:00:36.353 -> 332:  0x5F 0x81
13:00:37.336 -> 332:  0x61 0x82
13:00:38.353 -> 332:  0x61 0x82
13:00:39.338 -> 332:  0x61 0x82
13:00:40.355 -> 332:  0x61 0x82
13:00:41.339 -> 332:  0x61 0x82
13:00:42.353 -> 332:  0x61 0x82
13:00:43.334 -> 332:  0x62 0x82

My understanding is that orange is what's displayed and red is what the DME says is the actual redline. But it doesn't seem to actually enforce it.
Where RPM is: byte * 0x32 then convert to base10.

I am not sure what changing red would actually do.




One more data point from this morning. Car is fully cold, settings are changed as per first post;

09:23:06.448 -> 332:  0x46 0x78
09:23:07.433 -> 332:  0x46 0x78
09:23:08.453 -> 332:  0x46 0x78
09:23:09.439 -> 332:  0x46 0x78
09:23:10.459 -> 332:  0x46 0x78
09:23:11.445 -> 332:  0x46 0x78
09:23:12.464 -> 332:  0x46 0x78
09:23:13.450 -> 332:  0x46 0x78
09:23:14.437 -> 332:  0x46 0x78

3500 RPM orange, 6000 RPM red.

 

[RSL]

Been a long time since I had an M3, but I thought yellow and red rings were independent. Yellow was a soft limiter until at temp and red was hard, or at least a hard shift point for DCT. Maybe not.

 

[superwofy]

Been a long time since I had an M3, but I thought yellow and red rings were independent. Yellow was a soft limiter until at temp and red was hard, or at least a hard shift point for DCT. Maybe not.

I'm not sure if you mean physically independent? The yellow and red are on the same ring in the E9X M kombi - they rotate together.
Perhaps the red point is enforced by the DCT TCU?

It would be neat if the red actually worked. I'll set it really low and see if the DME limits - I doubt it.

I'm happy with the adjustment so far. Took the car this morning and the redline was displayed for quite a while. Before it was simply pointless. I made the setpoints even more aggressive.

 

[RSL]

For some reason, I thought the yellow and red weren't fixed together, like red would move higher rpm while yellow stayed low longer, but it's been like 10 years and I barely paid attention to it back then anyway.

I've pretty much talked myself out of M3 Kombi, but am getting sick of looking at the steering lock light when I turn on M mode. I might reconsider.

 

[superwofy]

For some reason, I thought the yellow and red weren't fixed together, like red would move higher rpm while yellow stayed low longer, but it's been like 10 years and I barely paid attention to it back then anyway.

I've pretty much talked myself out of M3 Kombi, but am getting sick of looking at the steering lock light when I turn on M mode. I might reconsider.

No, definitely together. For a long time I actually had a non-M kombi with the variable redline parts from an M3 one. I liked the amber better.
But once I figured out how to activate the shiftlights I got myself a DCT cluster.


Check this out if you want to fix just the M symbol:

BMW E90 E92 M3 Euro warning light panel

Euro warning light panel with icons insetead of "BRAKE" and "SERVICE ENIGNE SOON" for a cleaner look. Fits E9x M3 models. Custom logo (not illuminated) can be added for models without adaptive cruise control.

venoxy.com

 

[RSL]

That's a pretty slick and cheap option. Thanks!

 

[KClemente]

Yup I've used that variable redline for a while now and it's even in MSD80!

I even tried to set it to where it'll sweep back to a lower rpm when the coolant gets hot, but it never seemed to work

 

[superwofy]

I can confirm now that the 'red' area does nothing - it's not a DME redline. As RSL mentioned it's probably for the DCT TCU. KOMBI only uses 'orange'.

Yup I've used that variable redline for a while now and it's even in MSD80!

I even tried to set it to where it'll sweep back to a lower rpm when the coolant gets hot, but it never seemed to work

That's probably due to the warmup RPM set in the eeprom. Once it hits that, no more movement.

That's a pretty slick and cheap option. Thanks!

I got Venoxy stuff before. They're pretty good, I'd rate the quality somewhere at 90% (maybe they improved since I got stuff?). If you order it, let me know if you like it, I think I'll get one for spare clusters.

 

[RSL]

I saw afterward LMB335is noted elsewhere there's only a functional limiter on the M3 DME (and uses oil temp), so not much more than an indicator on MSD8x apparently.

 

[That4chanhackerguy]

Hate to bring this back from the dead however could this be included in the INA0S XDF i would expect the addresses to be differnt. I can post the public one here.