[manni22gp]

Good day everyone.

I'd like to dip into the collective knowledge of the members.

I have a 2024 M240i xDrive on order, due to arrive in October.

Unfortunately I was not able to order the "M Technology Package" or "track pack" (I think that's what it's generally known as) - which would have added the wider wheels, wider front tyres, brake and cooling upgrades, and fender-arch extensions - the options are not available for my market.

I've separately ordered the fender-arch extensions, and will be fitting MSS suspension, and changing the wheels.

The wheels is the subject where I'm stuck and unsure what to do - if I were to go 20", what would be the correct offset, width, and tyre size / profile to a. ensure rolling circumference is kept in check, and b. matches the dropped suspension and fender-arch extensions?

Thank you all in advance.

[Coconut]

Refer to this article from Apex:

https://apexwheels.com/fitment-guide...ment-guide#oem

[manni22gp]

I'm struggling to get a calculator that identifies the correct 21" tyres - any pointers?

[Wasp_Factory]

You want 20" per the first post or 21" per the second? Not seen anyone fit 21" to the G42.

Assuming you want 20", the first question is whether you want to go wider than the M Tech wheel option which is 245/35/19 front and 255/35/19 rear. I have this set up and it is plenty of tyre on a 240iX on the road.

If you want to go for 20", at these widths, you'd simply need to drop to 245/30/20 front and 255/35/20 rear. The Michelin MPS4S star would be a decent choice and keeps the car close to OEM spec.

For offset, I have aftermarket wheels and went with ET 20 at the front and ET 30 at the rear on Eibach lowering springs (-20mm f&r). I don't have the fender flares. I feel you could go to ET15 front and ET20 rear giving you an extra 5mm poke (fender flares are 4mm I think) and you'd have the perfect stance with as much poke as you can legally get away with. You need 66.6mm bore, otherwise you'll need spigot rings.

If you want to go wider, take a look at Motech Performance in the UK - they've gone wider at the rear on 20".

The above will keep you within the 1% rolling radius delta front to back but probably means that you will need to go the custom alloy route to get exactly the size, offset, colour, centre bore and bolt pattern that you need. This will allow you to use the centre caps off your OEM wheels as well.

Hope this helps.

[manni22gp]

Originally Posted by Wasp_Factory

You want 20" per the first post or 21" per the second? Not seen anyone fit 21" to the G42.

Assuming you want 20", the first question is whether you want to go wider than the M Tech wheel option which is 245/35/19 front and 255/35/19 rear. I have this set up and it is plenty of tyre on a 240iX on the road.

If you want to go for 20", at these widths, you'd simply need to drop to 245/30/20 front and 255/35/20 rear. The Michelin MPS4S star would be a decent choice and keeps the car close to OEM spec.

For offset, I have aftermarket wheels and went with ET 20 at the front and ET 30 at the rear on Eibach lowering springs (-20mm f&r). I don't have the fender flares. I feel you could go to ET15 front and ET20 rear giving you an extra 5mm poke (fender flares are 4mm I think) and you'd have the perfect stance with as much poke as you can legally get away with. You need 66.6mm bore, otherwise you'll need spigot rings.

If you want to go wider, take a look at Motech Performance in the UK - they've gone wider at the rear on 20".

The above will keep you within the 1% rolling radius delta front to back but probably means that you will need to go the custom alloy route to get exactly the size, offset, colour, centre bore and bolt pattern that you need. This will allow you to use the centre caps off your OEM wheels as well.

Hope this helps.

Hi Wasp.

Thank you for your reply.

I'm also considering 21", and more than likely going this route.

[Wasp_Factory]

Never seen 21s on a G42, so am interested to see where you go with this. When do you get your car?

You'd need to go down to a 25 profile tyre. This would be suicide in the UK due to the state of the roads, but perhaps they are better where you are. A quick search suggests that tyres are not available here in 245/25/21 or 255/25/21, so perhaps check this out before pressing the button on 21s. You could stick at 30 profile tyres, but you rolling radius would then be 25mm greater and your speedo would be out. Not sure if it would also throw some error codes.

The comments about widths and offsets above still apply. If you want a more aggressive offset and to drop it as low as possible on the MSS, you may need camber plates.

[manni22gp]

Originally Posted by Wasp_Factory

Never seen 21s on a G42, so am interested to see where you go with this. When do you get your car?

You'd need to go down to a 25 profile tyre. This would be suicide in the UK due to the state of the roads, but perhaps they are better where you are. A quick search suggests that tyres are not available here in 245/25/21 or 255/25/21, so perhaps check this out before pressing the button on 21s. You could stick at 30 profile tyres, but you rolling radius would then be 25mm greater and your speedo would be out. Not sure if it would also throw some error codes.

The comments about widths and offsets above still apply. If you want a more aggressive offset and to drop it as low as possible on the MSS, you may need camber plates.

I get the car at the end of October.
Roads here are ok, no problem with the 25 profile.

[bozo777]

Originally Posted by manni22gp

I've separately ordered the fender-arch extensions, and will be fitting MSS suspension, and changing the wheels.

Thank you all in advance.

Hey op, where did you find the fender-arch extensions, would you mind sharing the link for it? or was it through your dealer?

cheers

[manni22gp]

Originally Posted by bozo777

Hey op, where did you find the fender-arch extensions, would you mind sharing the link for it? or was it through your dealer?

cheers

Hey 777, humble apologies for the delayed reply - I got the arch-extensions from BMW parts (original).

[bozo777]

Originally Posted by manni22gp

Hey 777, humble apologies for the delayed reply - I got the arch-extensions from BMW parts (original).

I see, that's cool that is something you can add from BMW after the fact. If you don't mind op, how much did you end up paying for it? was it also paint matched to your car?

Cheers

[BG42]

running 20s def opens up quite a bit more wheel options. As for the the arches they come primed, think autoid used to sell them on their site for around $550 US.

[manni22gp]

Hi everyone.
Thank you for everyone’s input.
In the interim I received the car, finalised the design-concept, ordered the parts, and finally completed it yesterday.

Happy to answer any questions.

[NoDramaG42]

That looks incredible sir!
Beyond just the wheels, it looks like the color matched wrap is must have to fix the back end on these cars.
Did you end up with 20s?

[manni22gp]

Originally Posted by NoDramaG42

That looks incredible sir!
Beyond just the wheels, it looks like the color matched wrap is must have to fix the back end on these cars.
Did you end up with 20s?

Thank you!
I went with matte-ppf - the colour-coded side-skirts and rear-bumper inserts are peelable-paint in the original Brooklyn Grey.
I did end up going with custom 20" wheels - 21" proved to be very complicated with too many unknown variables.

[TopG42]

Originally Posted by manni22gp

Thank you!
I went with matte-ppf - the colour-coded side-skirts and rear-bumper inserts are peelable-paint in the original Brooklyn Grey.
I did end up going with custom 20" wheels - 21" proved to be very complicated with too many unknown variables.

Can you link the peelable paint?

[manni22gp]

Originally Posted by TopG42

Can you link the peelable paint?

Hi TopG42.
I'm not sure what you mean by linking it?

[TopG42]

Originally Posted by manni22gp

Hi TopG42.
I'm not sure what you mean by linking it?

Oh sorry! I meant can you provide a hyperlink to the site you purchased the peelable paint from

[manni22gp]

Originally Posted by TopG42

Oh sorry! I meant can you provide a hyperlink to the site you purchased the peelable paint from

I couldn't tell you I'm afraid - my BMW Bodyshop did it for me.