[2045]

Originally Posted by kjb914

Possibly a dumb question - will you need wider rims to accommodate wider tires or can you put the wider tires on the stock rims??

Normally you do but since stock wheels are wide enough to take wider tires so you can say BMW put the undersized tires on the stock wheels. Going to to fine in this case.

Would really like to know the reason behind the 265/40-21 choice on the X3M. For reference, X3M rear wheel is 10" wide vs 9.5" on the X3M40i, but the M40i has 275/40-21 tire. So they put wider tire on an narrower wheel for a less performer...

[2045]

Originally Posted by clickclickboom

265/40 & 295/35 incoming. They will be mounted on friday.

Can't wait to see them! in theory they should look perfect. Please post pics when done!

[Turbo1204]

Must I have spacers in the front to accommodate 265? Any input will help.

[MistaVauros]

Originally Posted by 2045

Can't wait to see them! in theory they should look perfect. Please post pics when done!

Different sidewall height in the rear? Why not keep it 295/40? Any potential issues with the transfer case?

[MistaVauros]

Originally Posted by Turbo0823

Must I have spacers in the front to accommodate 265? Any input will help.

Spacers are not required; purely optional if you want a wider look.

[2045]

Originally Posted by VAUROS

Different diameter in the rear? Why not keep it 295/40? Any potential issues with the transfer case?

running the 295/40 will increase the OD by over an inch. not ideal. It's default to go less in profile when going wide to keep the OD within spec.

[MistaVauros]

Originally Posted by 2045

running the 295/40 will increase the OD by over an inch. not ideal. It's default to go less in profile when going wide to keep the OD within spec.

Gotcha. Let us know how they drive/feel once you get them and provide a comparison to the PS4S' in terms of grip, handling, and braking.

Thanks!

[2045]

clickclickboom first lol.

[MistaVauros]

Originally Posted by 2045

clickclickboom first lol.

Oh snap! I always end up responding to the wrong post/member when I use the mobile app vs using desktop PC. 🤣

[MistaVauros]

How will running 12mm spacers effect the 295 tire in the rear in terms of ride quality, tire wear, and poke? I'd like to push the tires out to the fender a bit, but if the spacer would make the rear 295 poke out from the fender then I don't want that. I know the 15mm would make a 295 tire poke, but curious if the 12mm will...

[Ilyam5]

Originally Posted by 2045

Normally you do but since stock wheels are wide enough to take wider tires so you can say BMW put the undersized tires on the stock wheels. Going to to fine in this case.

Would really like to know the reason behind the 265/40-21 choice on the X3M. For reference, X3M rear wheel is 10" wide vs 9.5" on the X3M40i, but the M40i has 275/40-21 tire. So they put wider tire on an narrower wheel for a less performer...

Staggered set ups are done on passenger cars to induce under-steer - which is much easier for an untrained driver to deal with. They also make the steering lighter and less prome to tram-lining (following the road) which again for average grandma - is a god send.

M cars are usually aimed at enthusiast - so they try to provide neutral handling. that requires a square set up - equal contact patch on all corners or as close to it as possible.

Looks do not matter in performance. For higher performance you want - smallest possible rim that will clear the calipers and the stickiest tires possible with minimum weight.. UN-sprung weight is huge for performance.
You find some 19lb wheels with PS4 S light non RF tires - and the performance will sky rocket.
Huge 22" wheels and tires deteriorate performance and reduce ride comfort for the sake of looks.

Same with spacers - unless you are clearing brake caliper on a spare tire for 20 min drive - do not do it. Unnecessary strain on ball bearings is not good
Why try to re- engineer an M car that is set up for handling?

[MistaVauros]

Originally Posted by Ilyam5

Staggered set ups are done on passenger cars to induce under-steer - which is much easier for an untrained driver to deal with. They also make the steering lighter and less prome to tram-lining (following the road) which again for average grandma - is a god send.

M cars are usually aimed at enthusiast - so they try to provide neutral handling. that requires a square set up - equal contact patch on all corners or as close to it as possible.

Looks do not matter in performance. For higher performance you want - smallest possible rim that will clear the calipers and the stickiest tires possible with minimum weight.. UN-sprung weight is huge for performance.
You find some 19lb wheels with PS4 S light non RF tires - and the performance will sky rocket.
Huge 22" wheels and tires deteriorate performance and reduce ride comfort for the sake of looks.

Same with spacers - unless you are clearing brake caliper on a spare tire for 20 min drive - do not do it. Unnecessary strain on ball bearings is not good
Why try to re- engineer an M car that is set up for handling?

I partially agree with you on the handling design intention of M cars and that spacers are generally not good overall. However, in terms of tire width, the X3MC should come with at least a 285 rear tire option. I understand that it's not RWD selectable like the M5, so you could argue that wider tires in the rear are unnecessary. However, for an M car, especially for an SUV, a rear 265 just seems so outdated in this era of super sports vehicles. Common sport SUVs get 265 rear tires, but the X3MC is anything but common.

[2045]

Reasonable width spacer does not cause any harm nor affecting performance. Porsche for instance has been using them to fine tune fitment on different models straight from factory. Driving characteristic I could understand but running the narrower tire on a wider rim that gives the default stretch look is not ideal for me. Not trying to re-engineer anything here. Just trying to find the perfect balance for both archaistic & performance.

[yllwwgn]

Originally Posted by clickclickboom

265/40 & 295/35 incoming. They will be mounted on friday.

Pics please! Are they on yet, are they on yet? Haha

[12v_dub]

Originally Posted by clickclickboom

265/40 & 295/35 incoming. They will be mounted on friday.

pics?

[clickclickboom]

I started a new thread here
https://x3.xbimmers.com/forums/showthread.php?t=1675788