Damn! Was expecting it to be way more than that.

They're surprisingly cheap since they were/are used on a bunch of DCT-equipped BMW's for the last 8-10 years. I had bought one locally for $1600 about 2 years back that i ended up selling after i sold my old 135i. They're all over the place now for $1300-$1500.

Also helped by the fact that they are difficult to use in anything else than a BMW with the same gearbox. making the marked for used ones because of chrashed cars really small.

That's waaaay cheaper than anticipated! And progress looks great so far!

Holy shit. This is right up my wheelhouse. What trans controller are you using, if I may ask?

In for the engine height as well. My K24 probably can't go any higher.

Can you share more details on the trans controller? What does the trans use for inputs? Are they regular (12V) solenoids that engage particular gearsets/clutches?

This is awesome. I'm surprised that there is little excitement about it here. A Miata with a DCT was in my head for a long time and I was waiting for someone to finally engineer this out.

Can we get more details? Is there another place where you describe your project in more details?

Do you plan on creating a kit once you are done so other people can use this awesome solution?

Please give us more updates.

Nice work man, thanks for taking the time to document it.

Pretty damn slick swap here. Congrats on taking this on.

I want one with the TCU solution please.

I am also curious. As someone who owns a BMW with this transmission, it's my understanding the TCU determines clamping pressure of the clutches by the "torque request" made from the pedal to the DME.

Line pressure vs engine torque is half shift feel (shock vs response) and half durability. You don't want your luxury car slamming gears driving around a city. You also don't want slow lockup at WOT, because you will put a lot of heat into the clutches due to slippage.
It's pretty common to run bench engine dynos with automatic transmissions by actuating the solenoids with 12v power supplies. At work we literally don't even use a TCU sometimes and just have a row of power supplies we toggle to select gears. Assuming this is a race car, you can make this work with fairly crude methods. We've done it with the NSX 9DCT and a slew of 6/9/10 speed torque converter slushboxes.

I knew the first part, but thanks for the insider info on dynos and such!

Have to say, I'm very interested in this. The trans height and need to raise the engine is a concern though. Would be interested to see if any measure could be taken to minimize block relocation.
I can see one of these in Vegas running ST2 at 2350# & 300 average whp with Sonny behind the wheel on 245 A7's. Even if we got our asses kicked, I would love to build it and see it run.

Thanks for sharing Harald.

for a pure race car it might be the wrong transmission mainly because its a heavy bastard. and the ratios for most racecars would need a very tall rear end to keep the top speed down. but for a dual duty car that will see mostly street use and some trackdays i think its a great choice. low cruising RPM, quiet, and capable of handling any power a miata engine can make.

There really is no way of installing this without raising the engine Emilio. as the sump section of the gearbox actually sits a little lower than the BP sump. and that is with a gearbox sump of around 1/2" height.
you could probably make a new sump and save a few mm, but not more.

Here it is installed on the final transmission mount.

https://cimg5.ibsrv.net/gimg/www.mia...52f01b5074.jpg
https://cimg3.ibsrv.net/gimg/www.mia...cf96fdd343.jpg
https://cimg6.ibsrv.net/gimg/www.mia...f5d60eade8.jpg
https://cimg7.ibsrv.net/gimg/www.mia...827627adb2.jpg

Beautiful fab work!

Very cool idea

Sorry if I missed it, but how much did you have to raise the engine?
Any change to angle of engine?

I raised the engine 17mm. a DCT had never been tried in a mx5 so we didnt know anything about how it would fit until we tried :D the angle is still spot on.

https://cimg7.ibsrv.net/gimg/www.mia...ded79fcbbf.jpg
Custom 3" driveshaft made by a friend of mine installed. Perfect fitment:)

Nice
 

Good to see you got this off the ground.

I have the dev firmware for MaxxECU and the DCT wiring harness releases soon, to use the stock mechatronics with clutch kick feature as well. Less expensive and don't have to replace the factory BMW TCU!