Are N54 and N55 DCT interchangeable?


Brigadier General
Sep 6, 2017
Down Under @ madautodevelopments
S65 1m
Tom from jpl auto parts in seven Hills nsw Australia has done it on his 335i wagon, you might need a msd81 aswell not sure.

The car will have to be rewired for the dct shifter from the ecu, its a massive job.

Every car is a little different in terms of electronics and different versions of modules, its not one suits all.

Not sure if it can be done over the net via email.

Personally I'm going with the hp28 conversion as it will be stronger than any dct box and rebuilds are cheap and will cost half the price for something twice as strong


New Member
Aug 25, 2021
Ah yes the MSD81 I got that sorted out with Bimmer ECU Solutions. Thanks to VSOmar.

I will have to look up Tom and shoot him an email to ask some questions. I may have seen that thread possibly is it the one where the guy had a 328 wagon and he put in an N54 DCT? That build was insane.

The HP28 I looked in to that option aswell a while back I think guru autoworks was the one making the kit. Their adapter costs $1700 I belive. For drag racing a nice high stall converter in the HP28 is a no brainer. But for track use I prefer the DCT. The shifts are crazy fast and don't upset the balance of the car in a corner.