M1 tire sizes?

[dbtk]

What are the anticipated tire sizes (front and rear) of the new "M1"?

[Drillslinger]

Since it's using the same f/r track as the M3, wouldn't the M1 (1///M or whatever) use the same size tires?

[ptack]

We can only pray that is true, but the current 1 offsets are one-offs so don't be surprised if the uniqueness continues.

[oztiks]

275's up front and 305's in the rear ...

[Drillslinger]

Originally Posted by ptack

We can only pray that is true, but the current 1 offsets are one-offs so don't be surprised if the uniqueness continues.

Good point, but if they're reworking the wheel wells/fenders anyway....

[Cornhusker]

I vote 265/245. However I hope for 275/255. Aftermarket you'll be able to go at least two sizes bigger back/front so at least 285/265 I bet.

[amdmaxx]

How will the winter setup look?
Will M1 be terrible even with winter tires if they are on the wide side?

For summer, I would want to see a staggered deep dish setup.

[grant]

Originally Posted by amdmaxx

How will the winter setup look?
Will M1 be terrible even with winter tires if they are on the wide side?

For summer, I would want to see a staggered deep dish setup.

You'd definitely want to use a separate set of narrow wheels to go with your snow tires for best winter performance.

[BMW269]

I think M3 rims with M3 tires will fit. But it will maybe not go in to production with 19" but 18".

[///Mangler]

square 255/18 setup for me.

T

[BMW269]

Originally Posted by ///Mangler

square 255/18 setup for me.

T

Could you explain me the differences, pro/contra of 245 front/265 rear and 255 square?

[Cisitalia]

Originally Posted by Levi

Could you explain me the differences, pro/contra of 245 front/265 rear and 255 square?

Less understeer in a square setup. Also allows front:rear tire rotation that is especially usefull for when driving on the track. Allows for more even wear distribution. BMW won't do that though, since they want induced understeer for the bad drivers out there.

I would appreciate a square setup, but I would want it wider than 255. I think 275 square would suffice on this car.

[///Mangler]

Originally Posted by Cisitalia

Less understeer in a square setup. Also allows front:rear tire rotation that is especially usefull for when driving on the track. Allows for more even wear distribution. BMW won't do that though, since they want induced understeer for the bad drivers out there.

I would appreciate a square setup, but I would want it wider than 255. I think 275 square would suffice on this car.

This^^^, but 275 is getting heavy. You want unsprung as light as possible and if they can lighten the car 255 will suffice.

T

[BMW269]

Ok, thinks. But Audi has sqare setup and understeer. Is it because of AWD?

[Muffnbluff]

Originally Posted by ptack

We can only pray that is true, but the current 1 offsets are one-offs so don't be surprised if the uniqueness continues.

Not if they're just robbing the //M3 parts bin.

[Cisitalia]

Originally Posted by Levi

Ok, thinks. But Audi has sqare setup and understeer. Is it because of AWD?

Yes and those cars are front heavy which also induces an extra dose of understeer.

Originally Posted by ///Mangler

This^^^, but 275 is getting heavy. You want unsprung as light as possible and if they can lighten the car 255 will suffice.
T

Not quite, if that was the case people would put bicycle tires on. Yes less unsprung weight is an admirable goal but not at the expense of tire width. That single factor alone can greatly increase handling capability, but only to a point. There is an optimum and certain amount of compromising required. The handling benefits of 20mm wider tires are greater than loosing 2 pounds of unsprung weight per corner on this car (Mich PS2 255/35-18 25# vs. 275/35-18 27#).

If the car was 3000 lbs. and less than 300hp, than a square 255 setup would suffice. But this car begs for the square 275 setup, especially for the track. Hoosier R6 275/35-18 at 23# would be an awesome square setup for the track on some light wheels.

[JimD]

If we assume that the M1 is getting the M3 LSD rear end, it would turn higher rpm - for quicker acceleration and worse gas mileage - if it uses the same 265/40 series rear tires (because the M3 LSD is a 3.85 ratio versus the 3.08 of the 135). They could change the ratio but I wonder if they will with the M1 being, presumably, a limited volume vehicle. Rpm of this combination would be over 2500 at 60 mph - only a little lower than the M3 (which has a .87 6th gear versus .85 in the 135).

I don't know if they'll set it up this way, the 135 doesn't need the rpms to make power the way the M3 does, but it will be a very quick car if they do.

Jim

[///Mangler]

Originally Posted by Cisitalia

Yes and those cars are front heavy which also induces an extra dose of understeer.


Not quite, if that was the case people would put bicycle tires on. Yes less unsprung weight is an admirable goal but not at the expense of tire width. That single factor alone can greatly increase handling capability, but only to a point. There is an optimum and certain amount of compromising required. The handling benefits of 20mm wider tires are greater than loosing 2 pounds of unsprung weight per corner on this car (Mich PS2 255/35-18 25# vs. 275/35-18 27#).

If the car was 3000 lbs. and less than 300hp, than a square 255 setup would suffice. But this car begs for the square 275 setup, especially for the track. Hoosier R6 275/35-18 at 23# would be an awesome square setup for the track on some light wheels.

I don't think you will get 275's up front from BMW, plus those 2lbs are as far out as you can get on the wheels so you suffer momentum/braking losses also. These are things that have to be tested on track to find the happy compromise between grip and handling. Bigger is not always better.

T

[Cornhusker]

Originally Posted by Cisitalia

Yes and those cars are front heavy which also induces an extra dose of understeer.


Not quite, if that was the case people would put bicycle tires on. Yes less unsprung weight is an admirable goal but not at the expense of tire width. That single factor alone can greatly increase handling capability, but only to a point. There is an optimum and certain amount of compromising required. The handling benefits of 20mm wider tires are greater than loosing 2 pounds of unsprung weight per corner on this car (Mich PS2 255/35-18 25# vs. 275/35-18 27#).

If the car was 3000 lbs. and less than 300hp, than a square 255 setup would suffice. But this car begs for the square 275 setup, especially for the track. Hoosier R6 275/35-18 at 23# would be an awesome square setup for the track on some light wheels.

Agree, but I still bet on 265/245 stock.

[Cisitalia]

Originally Posted by ///Mangler

I don't think you will get 275's up front from BMW, plus those 2lbs are as far out as you can get on the wheels so you suffer momentum/braking losses also. These are things that have to be tested on track to find the happy compromise between grip and handling. Bigger is not always better.

T

Originally Posted by Cornhusker

Agree, but I still bet on 265/245 stock.

Totally agree. BMW will go stagger like you indicated. I am only thinking of a track setup.