Martyn's Z4M Coupe

[RMB]

Absolutely stunning Martyn.
I wish BMW still made cars as good looking as this and the E46 M3. It just doesn’t get any better than this, Z4MC on CSLs.
Taz there’s a set for sale on this forum.

[3gGT01]

Wow Martyn, that looks amazing!!! The silver color really pops! Not sure if you clay barred it or what, but it looks great. I would like to do some of the same mods you have done.

Where did you get that carbon fiber front splitter?
Just the right amount of splitter for a great looking street car. Not overly done like you might expect on a track car.

I ordered the front calipers you have and should be on there way this week. Would like to get the same coilovers you have, I see there is a 4-5 week lead time. At 112K miles, the stock struts are rough on bumps and also the 19" rims probably don't help me either.

Neat to see someone doing all this cool stuff to their M.

~Tom

[Martyn]

Thanks all.

The wheels are Atomic CSL reps from BM Autosport.

I gave it a quick machine polish as it was covered in crap and light marking where Ive been working on.

The splitter is from here: https://www.schmiedmann.com/en/product/ ... E8586EDCAR

[Martyn]

So for those debating whether the transmission tunnel is smaller than the E46 M3.....I can confirm it's not! The trans doesn't appear to be any smaller either!

For reference, Z4M ZF gearbox next to an inline 6 E9x DCT box.







You all know what's coming next.

Sprung flywheel.



And of course, the DCT box bolted up into the Z4M.



No hammering of the trans tunnel at all.

Even the E46 M3 DCT trans mount bolted up to the Z4M trans mounting bolt holes perfect.

I'm absolutely battered from rolling around on the floor under the car so more updates to come over the next few days.

[Ed Doe]

Honestly the most consistently interesting thread on the forum Martyn - hats off to you!

Looking forward to more updates as they come - personally DCT-ing my car isn't something I'd want to do but I'm fascinated to see the results you'll have!

[TomK]

So for those debating whether the transmission tunnel is smaller than the E46 M3.....I can confirm it's not! The trans doesn't appear to be any smaller either!

All super interesting as usual Martyn, well done! So it's a box from an i6 correct? I've seen the v8m3 dct box is fairly different dimensions to ours so that makes sense.
Any thoughts why they didn't use the zf instead of the getrag manual box if the trans tunnel is the similar dimensions? I guess there must be some peculiarity of the zf to prevent it? Or just cheaper more likely?

[1536Z4]

Even the E46 M3 DCT trans mount bolted up to the Z4M trans mounting bolt holes perfect.

Very interested in this Martyn and I hope this works out as you may remeber from this post viewtopic.php?t=130841

[XMetal]

I'm confused. Is that an E9x M3 DCT box or an E46 M3 SMG box? There's no such thing as an E46 M3 DCT

[Martyn]

I did a DCT conversion on my old E46 M3 so had some parts left over like a custom gearbox mount for a DCT box and E 46 chassis.

The DCT gearbox is an e92 335i DCT gearbox flashed with modified M3 GTS software.

[XMetal]

Gotcha - thanks for the clarification.

[RMB]

This is amazing, great work. Hope to see more updates and maybe some videos?

Does the Z4m have the same traction and stability control systems as the E46 M3 and are you doing anything in that department to handle the extra horses Martyn? I wonder if you could implement E92 or later systems which are superior to the old gen stuff.

[Vanne]

looks good man!

[Martyn]

Regarding traction / stability, as I'm not using the stock ECU any more DSC is totally defunct, I'm using MaxxECUs traction control setup which is much more advanced than the stock system (The MK60 the Z4M uses is very similar to the MK60 setup in the later E46 M3), which craps its pants any time I went near the throttle lol.

I didn't get much done yesterday, or today but I did manage to measure the required length for the prop so it could be shortened and have the yoke changed to suit the gearbox. I dropped it off to a friends engineering company to see what he can do with it.

I cut the yoke from a 335i prop, ready to be grafted to a donor Z4M prop.



Donor Z4M prop.



Next up was to fit the DCT shifter to the car, the holes for the shifter were already there, and in exactly the right places! I chucked in some rivnuts, bolted it down and tested the trim. It all fits, but the gaiter really needs re-trimming due to the bulk of the E92 M3 DCT shifter.



I also modified the wiring for the paddle shifters I'll be using so they mimic the resistance of the OEM E9x M3 paddles. I'm going to re-use the pins from the stock clock spring as I'll no longer be running the stock multi function steering wheel. Once I have the position of the steering wheel where I want it I'll crimp on some dupont connectors and connect them to the clock spring.



I hope to fit the inline thermostat for the gearbox and connect up the gearbox oil cooler lines tomorrow, then I can partially fill the gearbox. I won't completely fill the gearbox until I have some form of exhaust on for obvious reasons.

[LawrenceW]

Loving this thread, this is several levels above my spannering capability so slightly in awe…

[3gGT01]

Thanks all.

The wheels are Atomic CSL reps from BM Autosport.

I gave it a quick machine polish as it was covered in crap and light marking where Ive been working on.

The splitter is from here: https://www.schmiedmann.com/en/product/ ... E8586EDCAR

Great! Thanks for the info Martyn. Quite interesting stuff you are doing. Was doing my own tuning on my built 5.0L Mustang due to the expense for professional tuning on a dyno everytime I made a tweak... Really need a Dyno for tuning rather than collecting data on the street. Too expensive for a Dyno, unless tuning other cars to augment cost.