E46-engined E30 - Cruise-Control?

[Max S]

Hello everyone

I know that cruise control can be retro-fitted to an E30.
But has anyone ever pulled that off with an E46-engine?
I could imagine that to be a lot more difficult/complicated due to the gap in technology.

Thanks in advance,

Max

[cscracker]

The e46 cruise control is integrated into the ABS/DSC system. It uses the rear-right wheel speed sensor. The throttle is electronic and controlled by the computer. So, unless you're running a custom engine management system, or you've also swapped in e46 ABS/DSC, you're probably not going to be able to have cruise control. It may be possible somehow to provide the speed signal the DME needs without the ABS system, but you'd need to know a lot about how the electronics work on the e46. You should check e46fanatics, there's a few threads over there on custom tuning using the stock computer, and if anyone would know about it, they would.

[nando]

Actually, it's definitely possible. For one, most E46 DMEs can be configured to use a direct VSS signal (the one from the back of the E30 cluster, typically used for cruise control - works fine). Then you need a switch that will work with your DME (the Z3 and Z4 are good choices to look for that sort of thing, since they have bits of 'new' and 'old' tech in them).

What is usually missing is people don't set up the DME to work with the direct VSS input. Also, gtpeterson makes a CAN interface board that you could probably use to make this work with a different method. Another possibility is to upgrade to the MK60 ABS/DSC from an E46 M3.

[Max S]

Thanks!

Another possibility is to upgrade to the MK60 ABS/DSC from an E46 M3.

That might be the most practical option, since I'm already grabbing an engine and probably the gearbox (not sure which one to use) from that car, so maybe combining that might actually make the wiring a bit easier.

I haven't really had the Z4 on my radar yet (somehow thought that that was "a bit too modern", but the Z3 (and the E36 too, for 5-lug conversion) were already on my radar.
I'll surely check those options, maybe I end up with so many parts from one plattform/car that I just go and get a car to part out/"slaughter".

Max

[Caperix]

Actually, it's definitely possible. For one, most E46 DMEs can be configured to use a direct VSS signal (the one from the back of the E30 cluster, typically used for cruise control - works fine). Then you need a switch that will work with your DME (the Z3 and Z4 are good choices to look for that sort of thing, since they have bits of 'new' and 'old' tech in them).

What is usually missing is people don't set up the DME to work with the direct VSS input. Also, gtpeterson makes a CAN interface board that you could probably use to make this work with a different method. Another possibility is to upgrade to the MK60 ABS/DSC from an E46 M3.

How is the vss setup preformed? I know an e39 can be changed with coding due to the different engine setups installed, but I did not think that would work on an e46.

[OldManJames]

if you can try to somehow make the vacuum based m20 cc work on the m54, that would much much easier

[Max S]

Just an idea:
I plan on an S54 as my E30's engine.
I also plan a 5-lug conversion.
So the following thought popped up:
The BMW E85 Z4 (2006–2008) came with the S54 in the most powerful version, and it's avaliable with cruise control.
And Z4-hubs have been used to do the 5-lug conversion.
Shouldn't there be a way to "transplant" the speed-sensor from the rear right wheel along with the hub and get that to work (either with the E46's ECU or a custom one)?

Max

[nando]

The Z4 uses MSS70, which can run directly off the VSS from the instrument cluster - you don't need to mess with ABS sensors. However, I do not know how cruise control on it works, except I believe the DME handles it all. Perhaps it would work with a Z4 switch - probably best to study some wiring diagrams. :)

on MSS54, I don't think the cruise control is completely covered by the DME, but it can also run directly on the signal from the E30's cluster.

[gpeterson]

on MSS54, I don't think the cruise control is completely covered by the DME, but it can also run directly on the signal from the E30's cluster.

It is completely covered by the DME on MSS54. Previous statements (by others) about integration with DSC are incorrect. The DME needs a proper speed input (regardless of source), clutch/gear position switches, brake switch, and MFL inputs from steering wheel buttons or the stalk via interface part number 65718380054. There is a bit of info on the stalk interface at https://www.r3vlimited.com/board/sho...8&postcount=20.

[gpeterson]

if you can try to somehow make the vacuum based m20 cc work on the m54, that would much much easier

Probably not possible or safe. The DME won't be happy seeing something other than the actuator opening the throttle. Making it all work like factory on the S54 (and likely M54) is actually straightforward.

[nando]

M20 CC isn't vacuum based anyway. :)

[Max S]

Okay.
Sorry, but I got to throw in a stupid question.
What's the DME?

Other than that, I got to say that I don't really like the thought of "patching together the vacuum-system".

Max

[nando]

Digital Motor Electronics - basically, the german name for the ECU/PCM/Computer.

[Bimmerman325i]

I've done this.


I got the cruise control working in my S54'd E36.


Things you for sure need:
-E46-style clutch switch (3 pole, not 2 pole)
-Brake and Brake Test switches wired for an E46 (different from E36, annoyingly)
-VSS input. Doesn't have to be from Mk60 DSC, though I am using that one.
-MZ3 S54 cruise control box. Converts E36 cruise stalk signal into the MFL signal, which is wired directly to the ECU.


Once you have VSS figured out, along with brake/brake test/ clutch switches wired in and reporting correctly via INPA, connect the Z3 cruise box to the E36-style cruise stalk, then feed the cruise box power and ground, and then wire the MFL signal to the corresponding DME pin.


You may need to do some tweaking of the above for E30.


You do NOT need the gear position switch for cruise functionality. 100% do not. Nor do you need DSC Mk60-- S54 Z3M did not have Mk60, nor Mk20 iirc.

This is assuming you are using the MSS54 DME from an E46 M3 or Z3M. If you are using the Z4M DME, you're on your own in uncharted territory.

[terraphantm]

Things you for sure need:
-Brake and Brake Test switches wired for an E46 (different from E36, annoyingly)

This can be tuned out

The Z4 uses MSS70, which can run directly off the VSS from the instrument cluster - you don't need to mess with ABS sensors. However, I do not know how cruise control on it works, except I believe the DME handles it all. Perhaps it would work with a Z4 switch - probably best to study some wiring diagrams. :)

on MSS54, I don't think the cruise control is completely covered by the DME, but it can also run directly on the signal from the E30's cluster.

MSS70 handles it the same as all the other E46-era DMEs. And cruise control is 100% in the DME for pretty much all of BMW's DBW cars (probably with the exception of weird shit like the M73)