6MT to DCT swap

[amg6975]

Originally Posted by 2226cc

I see! Never knew stub lengths would make a difference tbh, I’ll just see how it goes and other I’ll just wire the canbus differently. I once seen someone connecting a pt can for the gearbox on the fuel pump module behind the back seat and that worked fine so I wasn’t really worried.

"Working" is a bad metric. CAN has at a protocol layer some protection against data corruption so if there are bit errors the data just doesn't happen. BMW then also does various data checks on packets around the car and will throw away packets that don't look right. That said, I doubt you'll notice any issues even if the car is throwing away packets.

Also, the fuel pump module is not on PT-CAN in the M3. It is on the non M cars though.

Build looks good. I like that you kept it so it's easy to return to stock. Nice work.

[M3SQRD]

Awesome swap. Attention to detail is beautiful. S65 pairs perfectly with the DCT.

[2226cc]

Just took it for the first test drive and DCT in combination with the 3.85 diff is so good!

Sadly cold and no traction at all but first testdrive was a Suc6!

[DrFerry]

Originally Posted by 2226cc

Just took it for the first test drive and DCT in combination with the 3.85 diff is so good!

Sadly cold and no traction at all but first testdrive was a Suc6!

That's great news. Glad all of your hard work and planning paid off. The engine sure sounds happy to rev - and that's a good thing. Maybe as a next step you might want to consider adding a Harrop Supercharger (positive displacement blower). I had one on my E92 M3 for ~6 years and 55K miles. The Harrop SC totally transforms the car by making the S65 V8 'think' it's an S85 V10. However, they've become very pricey nowadays though sometimes (rarely) used ones come up for sale on this forum. Just a thought... Thanks for the 1st test drive vid.
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[M3SQRD]

Originally Posted by 2226cc

Just took it for the first test drive and DCT in combination with the 3.85 diff is so good!

Sadly cold and no traction at all but first testdrive was a Suc6!

3.85 FD?

Congrats on the DCT swap! However, I have a diff with a 3.62 FD and I can’t imagine what it’s going to be like on a long drive, cruising in 7th gear. Frequent stops at the gas station!

[2226cc]

Originally Posted by DrFerry

That's great news. Glad all of your hard work and planning paid off. The engine sure sounds happy to rev - and that's a good thing. Maybe as a next step you might want to consider adding a Harrop Supercharger (positive displacement blower). I had one on my E92 M3 for ~6 years and 55K miles. The Harrop SC totally transforms the car by making the S65 V8 'think' it's an S85 V10. However, they've become very pricey nowadays though sometimes (rarely) used ones come up for sale on this forum. Just a thought... Thanks for the 1st test drive vid.
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I’m not sure about the supercharger, I’m more of a turbo guy definitely wanna keep this one na

[2226cc]

Originally Posted by M3SQRD

3.85 FD?

Congrats on the DCT swap! However, I have a diff with a 3.62 FD and I can’t imagine what it’s going to be like on a long drive, cruising in 7th gear. Frequent stops at the gas station!

Just gonna see how it goes, the 3.85 was already on the car so an easy choice. For now I love it!

[M3SQRD]

Originally Posted by 2226cc

Just gonna see how it goes, the 3.85 was already on the car so an easy choice. For now I love it!

Makes perfect sense. MT came with the 3.85 FD so why not try it. 1st gear pull must be a blast! The 3.62 FD was by far the best mod added to the car. I recommend Epic for the DCT software for cars with non-factory FD diffs. It addresses the non-upshift at redline in auto mode and vastly improved downshift throttle blips in all gears.

[Thumbie]

Wow you actually did it. Pretty awesome.

Not gonna lie I had my doubts haha. But it looks well done. cheers

[2226cc]

Originally Posted by Thumbie

Wow you actually did it. Pretty awesome.

Not gonna lie I had my doubts haha. But it looks well done. cheers

Thanks!

Car has been doing great, no canbus related or normal fault codes, shifting very smooth.

Never had a chance yet to give it a proper try tho, it’s cold and wet and with the short diff there’s just no grip, hoping for a good day soon so I can also use my dragy for some time measurements.

[DanMpower]

Great job man! The DCT is one of the few automatics that doesn't make me want to rip my hair out.

[torpid porpoise]

How's she holding up? I'm considering going down this path as well and would love to hear a semi-long term review.

[2226cc]

Originally Posted by torpid porpoise

How's she holding up? I'm considering going down this path as well and would love to hear a semi-long term review.

Car is doing great! No issues what so ever. Have done a few big trips. Fuel consumption obviously got worse but nothing out of the ordinary.

The only downside I would say is the 3.86 rear diff, especially on the autobahn it’s very frustrating as it’s just not as nice to drive fast.

But then also the thing i love about this is the 3.86 rear diff, the car is super quick, my friend has a e89 Z4 35is stage 2 so about 420hp and lots of torque also dct and we’re about the same, on the highway when the speeds get higher I’m pulling away

[sperkins]

Congrats on the swap !!
As an owner of a 6MT, and the more time I spend doing track days, the swap to DCT is very appealing.

Thank you for the inspiration.

-Steve

[Apatel]

Hey, sorry to bring up this old thread, but by any chance would you know the wiring pinouts etc you used? I am currently trying to do the same swap. Your help would be highly appreciated

[Apatel]

hi buddy, I am currently doing the same swap, and would like you guidance if you don't mind.

[M3_Legend]

This is crazy never thought I would see this swap. Hats off to you.

[Wulfspade]

I found this pinout for the shifter and drivelogic button, (use the right side for DCT).



The one thing I am missing is the pinout for these purple/black and purple/white wires on the side of the shifter. Does anyone know what these are for?

[amg6975]

That's the parking lock solenoid. On the stock car they run to do the DME box, and then down to the DCT. The DCT needs to see the solenoid or it will throw a CC-ID 540 error on the dash.

[Starboy]

Never thought I'd see people converting MT to DCT, but it's incredible.

I'll be converting my DCT to MT soon (waiting on pricing/parts).

Turns out if you always drive aggressively in the mountain roads, while using manual 95% on the DCT, the transmission will get overheated and malfunction. In my case the DCT won't shift into 1/3/5 and reverse ... such a pain in the ass

[tsk94]

Originally Posted by Starboy

Never thought I'd see people converting MT to DCT, but it's incredible.

I'll be converting my DCT to MT soon (waiting on pricing/parts).

Turns out if you always drive aggressively in the mountain roads, while using manual 95% on the DCT, the transmission will get overheated and malfunction. In my case the DCT won't shift into 1/3/5 and reverse ... such a pain in the ass

The DCT overheating issues are easily addressed with upgraded cooler and/or larger DCT pan. Lots of info on it in the track sub-forum, many hardcore (and fast) guys tracking & racing DCT's.

[Helmsman]

Originally Posted by Starboy

Never thought I'd see people converting MT to DCT, but it's incredible.

I'll be converting my DCT to MT soon (waiting on pricing/parts).

Turns out if you always drive aggressively in the mountain roads, while using manual 95% on the DCT, the transmission will get overheated and malfunction. In my case the DCT won't shift into 1/3/5 and reverse ... such a pain in the ass

Also various threads on over heating that isn't necessary due to...over heating. If you haven't already I'd check the basics i.e. fluid/filters, read the built in temps sensors to see that they actually align when over heating. If one sensor is going bad it will generate a code/limp mode as if fluid is over heated.
Far from an expert here but believe the car will go in limp mode first if due to over heated rather than start missing gears..?