MaxxECU cracked the DCT

DirtKurt

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Nov 5, 2016
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AFAIK it’s about the same as dkgecu.

No, just followed their updates on facebook etc.

I’m by no means advertising any system, just bringing up all the alternatives. :)

Its sounds promising, definitely going to check it out more. Somehow had never run across them
 

aus335iguy

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Nov 18, 2017
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@doublespaces this could probably use its own thread ?

Interesting that whifbitz chose to use them given they’d previously directly controlled the box directly using sivecs. Could the control measaging be that different ?
Also interesting is they claim the m4 box is smaller vs the E90 one.
 
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Svmp

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Dec 23, 2019
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@doublespaces this could probably use its own thread ?

Interesting that whifbitz chose to use them given they’d previously directly controlled the box directly using sivecs. Could the control measaging be that different ?
Also interesting is they claim the m4 box is smaller vs the E90 one.
The control messaging is quite different, i’m digging into it atm.
E-series 35i boxes are exactly the same length as F-series M4-boxes, i have both and have done measurements side to side. They probably are talking about the E9x M3 box vs F-series and there’s of course a difference because of the V8-bellhousing vs I6-bellhousing.
 
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stevieturbo

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Dec 26, 2019
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@doublespaces this could probably use its own thread ?

Interesting that whifbitz chose to use them given they’d previously directly controlled the box directly using sivecs. Could the control measaging be that different ?
Also interesting is they claim the m4 box is smaller vs the E90 one.

I believe previously they controlled the box directly with the Syvecs with some custom code options. Developing that would be a lot more time consuming and difficult....and also limited to that ecu, than a standalone transmission controller would be. So less appealing to a lot of customers if they had to purchase the ecu too.

The HTG controller is universal, and GZRacing say it can be used with pretty much any transmission. So if they're sorting a lot of the control aspects in the background, that would make it a much more marketable option for everyone. Sellers, installers, end users.

It really makes a lot of sense as it can be used on any car, with any ecu. Not just one specific ecu.

I'm looking to do a DCT swap myself, and need to decide whether HTG or DKG is the best option. Maxx ECU have obviously done a ton of work too, but I don't think they offer a trans controller as a separate unit ? and not sure it would make sense to buy an engine ecu just to use for trans control. I use Syvecs for engine control, and that will not change under any circumstances.
Certainly if Maxx offered a trans controller as a standalone unit....I would be very interested. Especially if they feel theirs can help tolerate a lot of power ( I'm twin turbo LS )

Still confused as to which box will be strongest to use though
 

Svmp

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Dec 23, 2019
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At the moment there are those three options:
- MaxxECU (Control via CAN just like OEM, no physical modification needed to gearbox)
- HTG GCU (Control via own system, modification of gearbox needed, original hardware removed)
- DKGECU (same type as HTG)


So, with all those three alternatives being about the same price, it really depends on what you are going for and what you already have. With MaxxECU you get engine control and TCU in one box, and retain the original functions/electronics of the DCT, meaning it is still fully functional to revert or install to any stock car if needed. Downside at least at the moment is only E-series is going to be supported.
DKGECU and HTG can do all boxes as they just replace the control electronics with their own.

In means of which controls the gearbox the ”best way” is surely debatable, and i dont think there are many people who have tested all three, so i’m not going into that.

I’ve tested the MaxxECU on my M50 turbo and it works great, handles likes stock and holds the little amount of power the car makes (800hp/840nm). I’m building another DCT at the moment and it’s from an M4, so i will maybe test HTG or DKGECU for that one.
 

stevieturbo

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Interesting....they did actually send me instructions the other day, but I hadn't looked at them yet. I wasn't aware they/DKG needed internal modifications to the box's mechatronics wiring.
Just looking at it now, and seems there are a number of re-wiring jobs to be done.

This certainly makes the Maxx route more appealing, although it'd still only purely be for transmission control for me. Whether this would then be easy to interface with the main engine ecu for torque reductions/throttle blips etc during shifts....is another matter. As it would never really be designed with that in mind.
 

Svmp

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Dec 23, 2019
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Interesting....they did actually send me instructions the other day, but I hadn't looked at them yet. I wasn't aware they/DKG needed internal modifications to the box's mechatronics wiring.
Just looking at it now, and seems there are a number of re-wiring jobs to be done.

This certainly makes the Maxx route more appealing, although it'd still only purely be for transmission control for me. Whether this would then be easy to interface with the main engine ecu for torque reductions/throttle blips etc during shifts....is another matter. As it would never really be designed with that in mind.
In MaxxECU you have all the DCT runtime values as variables so you can easily couple them to any digital output or CAN message that the main control unit accepts, in this way MaxxECU is indeed very flexible.

Of course there’s also downsides when using all OEM control; you need to have the correct GWS (gearshift lever) so that the communication works, and on E-series boxes that of course means that if you go for example with a 335 gearbox and lever, you can’t have the GTS software with the fastest shifts, while the ”aftermarket TCU’s” go with any kind of shift lever and shifts exactly as programmed.
As stated in the beginning of this thread, MaxxECU cracked the dct, that hopefully means we will have a commercial option (like xhp) to flash custom bins to the dct soon. That again will result in possibilities to have GTS speed shifting on a otherwise physically 335 gearbox WITH 335 GWS, this is something i’m looking forward to, because i just don’t like the appearance of the M3 GWS, doesn’t fit too nicely in the old E36 interior.:)
 

Pete_E30

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Nov 11, 2019
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I’ve tested the MaxxECU on my M50 turbo and it works great, handles likes stock and holds the little amount of power the car makes (800hp/840nm). I’m building another DCT at the moment and it’s from an M4, so i will maybe test HTG or DKGECU for that one.

I am running an SM4 ECU at the moment, but I'm considering swapping to a MaxxECU because the SM4 is old like DOS - even though it is very capable and has never given me any trouble. The Maxx has so many nice features; built in WB02, E-Throttle, USB, CAN, flex fuel, and a modern GUI.

The E-throttle interests me a lot because it can rev match the throttle on DCT downshift, but how this would tie in with DKGECU, I don't know. Given that my DCT is an F80, the Maxx won't be controlling it.

SVMP - Good to see another M50 turbo here! I'm running an M50B28 with an S256 Borg but only making 480whp. The 256 is tapped out!
 

stevieturbo

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Your shift selector ( paddle, whatever ) would send a signal to the DCT controller and also engine control ecu. So from that, whether an upshift or downshift signal, the ecu/tuner will decide whether cuts are required or a throttle blip.

Although when I asked about the DKG, they only seemed to offer a ground signal on "shift", and no distinction between up or down, which would be less than ideal for correct blips or cuts, as the engine ecu must know whether it's an upshift or downshift in order to respond correctly.

Unless I picked him up wrong on that, but sure that's what he said. Although with a suitable ecu and shifter, you should be able to send that raw signal to the ecu to initiate any cuts or blips.

Not sure what feedback is given to the engine ecu though as to gear position confirmation.

There's a lot to be said for one box controlling all this as the OEM do.
 
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fmorelli

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@doublespaces ... any benefit to splitting some of this out to a new thread? Visibility would be a plus, especially if getting names together. I've got a few DCT n54 guys that don't live here, and I'm point them to this.

Filippo
 

amg6975

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Your shift selector ( paddle, whatever ) would send a signal to the DCT controller and also engine control ecu. So from that, whether an upshift or downshift signal, the ecu/tuner will decide whether cuts are required or a throttle blip.

I don't think this is exactly true, but I could be wrong... The shift signal only goes to the transmission controller. That then sends a torque demand to the ECU based on if it the revs should go up or down, the ECU then blindly obeys, the TCU waits until the RPM is in the right window, releases the next clutch and lets the ECU return to normal operation. This is why the different flashes, and different transmission modes, can rev match more or less aggressively. It's all coordinated by the transmission controller.

The DSC can also change the torque demand for power intervention and launch control.

That's what I've gathered so far in my mission to sort out the meat of the PT-CAN bus.

EDIT: This is how the BMW systems interact. Just realized you may be talking about the MaxxECU, however I don't know why it would be different.
 
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Svmp

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I don't think this is exactly true, but I could be wrong... The shift signal only goes to the transmission controller. That then sends a torque demand to the ECU based on if it the revs should go up or down, the ECU then blindly obeys, the TCU waits until the RPM is in the right window, releases the next clutch and lets the ECU return to normal operation. This is why the different flashes, and different transmission modes, can rev match more or less aggressively. It's all coordinated by the transmission controller.

The DSC can also change the torque demand for power intervention and launch control.

That's what I've gathered so far in my mission to sort out the meat of the PT-CAN bus.

EDIT: This is how the BMW systems interact. Just realized you may be talking about the MaxxECU, however I don't know why it would be different.
I agree with you regarding the OEM PTCAN, looks like that indeed is the control strategy. To be more specific talking about OEM, regardless of E or F-series, shifting with the shifter itself, CAN-messages are sent, which the DCT listens to, because obviously the shifter and DCT are connected only via CAN-bus (okay, a LINbus for backup on E-series, and dual CANbus on F-series).
When shifting with flappy paddles, on E-series they are directly connected to the DCT via wiring harness and they work on varying output voltage, simple.
On F-series, the paddles are connected to FEM-module via LIN-bus (i think there was another module in between to convert the voltage to LIN) which in turn sends CAN-messages for shifting request to the DCT which then handles the rest.
 
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