Is it possible to make an auto Z4MR?

gadgetJunky72 · Post by **gadgetJunky72** » Thu Aug 27, 2020 1:24 pm

Hi Folks,

So I've recently had the itch to get my 6th (maybe 7th) Z4. If i could i would get an M roadster, but i'm unable to drive manuals due to back issues. I've had 3 x E89 35i and 1 x E89 35iS so thought i'd go back to an E85. Also partly because they are cheaper and I've just bought a new Supra. I'm also quite up for doing a project car.

So my question is what makes an M roadster special and can i replicate it in a non-M project car. I was thinking of starting with an auto 3.0si and changing the suspension, air intake, exhaust, engine tune to get me to maybe 80-90% of an M roadster.

Or am i just throwing money away?

Thanks

Pav

pvr · Post by **pvr** » Thu Aug 27, 2020 1:27 pm

If it is to keep, then it is fine to throw money at it. As a project to sell on - forget it, any "M" look-alike car never sells for the price that it has cost to get to that point.

mmm-five · Post by **mmm-five** » Thu Aug 27, 2020 1:50 pm

Would it not be simpler to put the gearbox from an auto Z4 (GA6HP19Z) into the Z4M (the manual gearbox in both is a GS6-37BZ/DZ), than trying to put all the Z4M bits onto a non-M?

R60BBA · Post by **R60BBA** » Thu Aug 27, 2020 1:56 pm

You could probably swap an SMG into the Z4M.

However it would make much more financial sense to buy buy an SMG E46 M3 Cab instead.

brillomaster · Post by **brillomaster** » Thu Aug 27, 2020 2:10 pm

Surely the thing that makes a z4m special is a proper M engine. Wheels and suspension are easy to change to suit.

That said, it would surely be easier to buy a z4m roadster and swap in an autobox, than buy a 3.0si and swap in an S54 engine... if you do that, might as well buy a 2.2i auto as a starting point.

And if you arent that fussed by the engine, then just go for a 3.0si auto. Still a quick car.

But no, a modded m54 or n52(?) Engine will never replicate a full fat S54 engine.

buzyg · Post by **buzyg** » Thu Aug 27, 2020 3:18 pm

mmm-five wrote: ↑Thu Aug 27, 2020 1:50 pm Would it not be simpler to put the gearbox from an auto Z4 (GA6HP19Z) into the Z4M (the manual gearbox in both is a GS6-37BZ/DZ), than trying to put all the Z4M bits onto a non-M?

This has to be the only real viable way to achieve what you are after. It will require time and money to do though. So as you say your budget is limited along side your new Supra, may be a none starter.

Starting with any other E85 there would be so much to buy and swap over, that it makes no sense at all from here.

Body panels and badges
Wing mirrors
Engine
Exhaust system, routed differently under the car too, so several more bits needed under there.
Suspension
Brakes
Wheels
Power steering system
Steering wheel
Even those lovely ///M logo-ed sports seats.

Oh and the gear nob

Mister T · Post by **Mister T** » Thu Aug 27, 2020 4:05 pm

A better option would be to convert an M Roadster to DCT.

Places like https://htg-tuning.com/ do standalone DCT controllers, so shouldn't be all that difficult.

groovy_hippy · Post by **groovy_hippy** » Thu Aug 27, 2020 4:11 pm

I know someone who converted an SMG E46 M3 from auto to manual (it's now a track car), it surely it must be possible to go the other way!

mmm-five · Post by **mmm-five** » Thu Aug 27, 2020 4:18 pm

Mister T wrote: ↑Thu Aug 27, 2020 4:05 pm A better option would be to convert an M Roadster to DCT.

Places like https://htg-tuning.com/ do standalone DCT controllers, so shouldn't be all that difficult.

Looks like they require an OE roboticized manual transmission (or an auto) on the car in the first place, and their ECU just replaces the OE one so that you can customise it.

Mister T · Post by **Mister T** » Thu Aug 27, 2020 4:21 pm

And a conversion kit for the GS7D36SG gearbox

https://www.facebook.com/adamatperforma ... 8981901836

Mister T · Post by **Mister T** » Thu Aug 27, 2020 4:23 pm

mmm-five wrote: ↑Thu Aug 27, 2020 4:18 pm
Mister T wrote: ↑Thu Aug 27, 2020 4:05 pm A better option would be to convert an M Roadster to DCT.

Places like https://htg-tuning.com/ do standalone DCT controllers, so shouldn't be all that difficult.
Looks like they require an OE roboticized manual transmission (or an auto) on the car in the first place, and their ECU just replaces the OE one so that you can customise it.

It's a standalone gearbox controller, they have BMW DCT gearboxes fitted to all sorts of different engines (2JZ, 1UZ, HEMI, LSX, etc.).

ph001 · Post by **ph001** » Thu Aug 27, 2020 4:31 pm

The peak torque to weight ratio of the 3.0Si and M are virtually identical:

3.0Si - 0.181 lbft/kg
Z4M - 0.186 lbft/kg

...so it's really only after 5000 rpm where you will really feel the difference in an M. I think the noise from the 3.0Si with the resonator is just as good and it's a whole lot smoother to drive as a daily. Of course the M has other benefits like hydraulic power steering but I would say you get 90% of the experience in a 3.0Si and you can have an auto right out of the box.

mmm-five · Post by **mmm-five** » Thu Aug 27, 2020 4:32 pm

Mister T wrote: ↑Thu Aug 27, 2020 4:23 pmIt's a standalone gearbox controller, they have BMW DCT gearboxes fitted to all sorts of different engines (2JZ, 1UZ, HEMI, LSX, etc.).

Sorry, thought you were suggesting the controller was all that was needed

A DCT would be nice for the motorway/city centre commute.

mmm-five · Post by **mmm-five** » Thu Aug 27, 2020 4:33 pm

ph001 wrote: ↑Thu Aug 27, 2020 4:31 pm The peak torque to weight ratio of the 3.0Si and M are virtually identical:

3.0Si - 0.181 lbft/kg
Z4M - 0.186 lbft/kg

...so it's really only after 5000 rpm where you will really feel the difference in an M. I think the noise from the 3.0Si with the resonator is just as good and it's a whole lot smoother to drive as a daily. Of course the M has other benefits like hydraulic power steering but I would say you get 90% of the experience in a 3.0Si and you can have an auto right out of the box.

You can have 90% of the fun with a dead Victoria Coren Mitchell as you can with an alive one - but I think I'll take the non-necro option

Post by **srhutch** » Thu Aug 27, 2020 6:38 pm

groovy_hippy wrote: ↑Thu Aug 27, 2020 4:11 pm I know someone who converted an SMG E46 M3 from auto to manual (it's now a track car), it surely it must be possible to go the other way!

That’s different as the gearbox is not replaced, just modified to manual, but there was never an SMG for the Z4///M.

My understanding on the Z4///M gearbox is that space is very limited so not sure what options are available.

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