maximum rear tire width

[arucano]

Given the limits on rear traction under acceleration, what is the larges practical 20" size tire/rim that can be fitted to an F06 M6 without modifications?

[BMWDriverX]

Originally Posted by arucano

Given the limits on rear traction under acceleration, what is the larges practical 20" size tire/rim that can be fitted to an F06 M6 without modifications?

You can run the 315/30/20 Toyo R888 and that's the widest you can go on the 10.5" rear. You won't be having traction issues after you put on those tires, unless it rains

[mastatikle]

Originally Posted by SoCalM6GC

You can run the 315/30/20 Toyo R888 and that's the widest you can go on the 10.5" rear. You won't be having traction issues after you put on those tires, unless it rains

I thought 305 is the widest on a 10.5 without too much sidewall flex?^
Depends on the wheel width, I'm running a 12.5 wide and a 325 tire with no rubbing (CP so it's a little lower too). Offsets play a factor also. I could prob go 335. If traction is your primary concern, drop rear to a 19 and use a soft drag compound. "Hook" is all in the sidewall with these torque monsters. Tall and soft sidewall and she'll bite. Bye bye to tread life.

[BMWDriverX]

Originally Posted by mastatikle

I thought 305 is the widest on a 10.5 without too much sidewall flex?^
Depends on the wheel width, I'm running a 12.5 wide and a 325 tire with no rubbing (CP so it's a little lower too). Offsets play a factor also. I could prob go 335. If traction is your primary concern, drop rear to a 19 and use a soft drag compound. "Hook" is all in the sidewall with these torque monsters. Tall and soft sidewall and she'll bite. Bye bye to tread life.

I used to run a 315/35/20 on a 20X10 and had no issues under hard acceleration in a Saleen Extreme pushing over 650hp. If you can run a 305 on a 20X10 you can run a 315 on a 20X10.5

[brad850csi]

Originally Posted by mastatikle

I thought 305 is the widest on a 10.5 without too much sidewall flex?^
Depends on the wheel width, I'm running a 12.5 wide and a 325 tire with no rubbing (CP so it's a little lower too). Offsets play a factor also. I could prob go 335. If traction is your primary concern, drop rear to a 19 and use a soft drag compound. "Hook" is all in the sidewall with these torque monsters. Tall and soft sidewall and she'll bite. Bye bye to tread life.

What offset are you running with that setup?

[M6-Coupe]

First of all you need to know the offset beside the width of your tire.
Second, unless if you just want to use your car just for rag purposes, having those wide tires will change all the suspension / camber calculations and you will feel huge under-steering and can't enjoy MDM mode at all
You will definitely get better traction if you install the softer compound tire at 305/30/20 size ; however you need 10.5" wide wheel.

[mastatikle]

Originally Posted by M6-Coupe

First of all you need to know the offset beside the width of your tire.
Second, unless if you just want to use your car just for rag purposes, having those wide tires will change all the suspension / camber calculations and you will feel huge under-steering and can't enjoy MDM mode at all
You will definitely get better traction if you install the softer compound tire at 305/30/20 size ; however you need 10.5" wide wheel.

When you say "can't enjoy MDM" the only time I use it is from a stop or straight pull, when I get any angle it kills power. Do you have it on in turns? If so does it let you drift at all or does it cut power quick in hard turns in which case I feel like that could be dangerous. Sometimes you need power to save a car through a drift.

[mastatikle]

Originally Posted by brad850csi

What offset are you running with that setup?

Don't hold me to it but if I remember right +22 in the rear. It's a flush setup.

[brad850csi]

Great, thanks for the response. I had worked out that around 20mm would be right for 325mm wide tires.

[M6-Coupe]

Originally Posted by mastatikle

When you say "can't enjoy MDM" the only time I use it is from a stop or straight pull, when I get any angle it kills power. Do you have it on in turns? If so does it let you drift at all or does it cut power quick in hard turns in which case I feel like that could be dangerous. Sometimes you need power to save a car through a drift.

Well when I had my M6 in MDM mode I could drift her on turns and it was not just this. Under hard acceleration MDM let some freedom to the tail to be happy

[mastatikle]

Originally Posted by brad850csi

Great, thanks for the response. I had worked out that around 20mm would be right for 325mm wide tires.

on a 12.5 wide wheel a 325 is stretched a little bit. On the lift I still had like an inch of room on the inside of wheel well. If I have extra money laying around I might try a 355 for shxt and giggles. Tire price is like $1000 a piece though lmao. Would kill performance but look amazing from the rear.

[arucano]

Originally Posted by brad850csi

What offset are you running with that setup?

standard 10.5 right now

[brad850csi]

Originally Posted by mastatikle

on a 12.5 wide wheel a 325 is stretched a little bit. On the lift I still had like an inch of room on the inside of wheel well. If I have extra money laying around I might try a 355 for shxt and giggles. Tire price is like $1000 a piece though lmao. Would kill performance but look amazing from the rear.

Makes sense as the M5 has the same suspension and stock rear offset is 34mm. People run 305s on wheels around 28-35mm offset. I always wanted 335/30r20 tires which exist in Michelin PSS for Porsche (I think the Carrera GT) but with the PS4S coming out I'm thinking about the La Ferrari spec 345/30r20 which I think will work with 20-25mm offset wheels

[brad850csi]

Originally Posted by arucano

standard 10.5 right now

On the stock wheels your best option will be 305/30r20 PS4S or PSC2

[ace32x]

Originally Posted by SoCalM6GC

You can run the 315/30/20 Toyo R888 and that's the widest you can go on the 10.5" rear. You won't be having traction issues after you put on those tires, unless it rains

running the 315 30 20 r888r on a 20x11 in the back of mine now with no rub. spins leaving out of second a smudge with bolt ons and tune still though. but traction greatly improved