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[Crypty]

Hey guys. I'm really don't know much about tire sizes and this is my first time ordering a new set for the M3.

I want to go with Michel Pilot Super Sports. What is the best size to go with for the stock 220M rims? Should I go 10mm wider all around? Keep it stock sizes?
I do a lot of autocrossing so I'm looking to get as much grip as possible on these street tires until I can pony up for a dedicated race set.

Thanks!

[Ashley Schaeffer BMW]

I went with 295 which is very wide for these wheels. Only because they didnt make 285 in that size. I like the wider tire look.

[rjd598]

I think for the track people here would recommend 255/275

[crispy tofu]

to answer your question, yes 10mm wider than stock is safe to use on your car and may provide additional grip. keep in mind that small bit of extra grip may come along with a small bit of less steering response due to the tire being oversized for the wheel.
when you're ready to spend on wheels, folks typically upsize to 275 square or 275 front, 295 rear.

[SouthShoreM3]

I have the conti 5Ps on my stock tires and the size is 255/35 in front and 285/30 in the rear. The fit very well and are a tremendous tire in my opinion. You do need to get them heated up when you drive or they can be a bit greasy.

Great in the rain as well and have lasted quite a while considering Ms eat tires

[Brucewonder]

what if you have 12.5mm spacers on?

[sonic03inSC]

Originally Posted by JAM3S

I went with 295 which is very wide for these wheels. Only because they didnt make 285 in that size. I like the wider tire look.

Can you post some pics?

[Dave07997S]

Originally Posted by JAM3S

I went with 295 which is very wide for these wheels. Only because they didnt make 285 in that size. I like the wider tire look.

A 295 on a 9.5" rim, this isn't the recommended minimum rim width for this tire. A 10" rim is the minimum for a 295 tire.

Dave

[Ashley Schaeffer BMW]

Well, I have that size tire on my wheels soooo...............

Thanks for stopping by.

[Ashley Schaeffer BMW]

Originally Posted by sonic03inSC

Can you post some pics?

[Denk]

I'd stick with stock for their light weight and handling. It's the right size for 220m's. Anything beyond +1 isn't optimal. Until you up your wheel size, I'd stick with stock size tires on 220's.

[M3takesNYC]

With stock power, I do not believe larger tires provide any actual grip in cornering or handling and in my view technically decreases things unless you have a power bump where traction is limited by the torque of the wheel rather than the slip angle which with stock tires and wheels, once moving you never are limited by wheelspin traction which tells you the tires are plenty wide.

Fatter tires do not offer better road hugging cornering ability. They provide a tire to not start spinning and smoking under cornering as would happen with a high horsepower car where fat tires helps keep traction in general which means better traction around corners because as we know, spinning tires around turns swings the back out and decreases traction in the spinning tires.

You add extra rotational and unsprung weight by adding bigger tires. 285s add 3 pounds to the tire atleast at the outermost part of the tire which means the most significant effect on rotational accereration.

At the end for stock power or even a bit beyond, the stock tires provide the lowest weight tire with the proper amount of sufficient grip to keep the tires planted.

You only knock performance if you increase. The GTS has more torque and almost 50 more HP which makes sense why it uses a bigger or wider setup

[pbonsalb]

Buy lighter, wider wheels and run wider tires. If stock 8.5/9.5 wide wheels, I would stick with no more than +10mm tire width. If competition 9/10 wide wheels, no more than +20mm width.

But consider what BMW did on the competition package -- they ran wider wheels but left the same tire size. The wider wheels have the effect of firming up the sidewall while also slightly increasing tread contact patch.

[gatorfast]

Stick with stock sizes

[slicer]

Originally Posted by M3takesNYC

With stock power, I do not believe larger tires provide any actual grip in cornering or handling and in my view technically decreases things unless you have a power bump where traction is limited by the torque of the wheel rather than the slip angle which with stock tires and wheels, once moving you never are limited by wheelspin traction which tells you the tires are plenty wide.

Fatter tires do not offer better road hugging cornering ability. They provide a tire to not start spinning and smoking under cornering as would happen with a high horsepower car where fat tires helps keep traction in general which means better traction around corners because as we know, spinning tires around turns swings the back out and decreases traction in the spinning tires.

You add extra rotational and unsprung weight by adding bigger tires. 285s add 3 pounds to the tire atleast at the outermost part of the tire which means the most significant effect on rotational accereration.

At the end for stock power or even a bit beyond, the stock tires provide the lowest weight tire with the proper amount of sufficient grip to keep the tires planted.

You only knock performance if you increase. The GTS has more torque and almost 50 more HP which makes sense why it uses a bigger or wider setup

I don't agree with you. My understanding is that wider tires can provide better lateral grip. The shape of the contact patch changes to a more horizontal oval. Why do you think race cars have fender extensions and wide tires front and rear? It's not only for wheel spin reasons. It's for lateral grip. Tires can also adjust certain handling characteristics of the car (just like suspension can). For example - Changing to tire widths in the front that more closely match the rear will reduce under-steer. Making that change is best done with a corresponding adjustment to wheel widths. Did you ever notice that Porsche specs 911's with 295's in the rear and 235's in the front? A base 911 has just over 300 hp. The 295's are not there for wheel spin. They are there because the car is rear weight biased. The extra width adds lateral grip, which helps dial out oversteer - making the car more neutral handling. Again... Wider tires require wider rims to support the width /sidewall. I wouldn't go with super wide tires without adjusting the wheel width.

[slicer]

Originally Posted by JAM3S

Well, I have that size tire on my wheels soooo...............

Thanks for stopping by.

Just because you can fit 295's on the wheels that does not mean its right... I can post some pictures of people fitting 205's on 9.5" wheels for the "stretched" look. That doesn't make it a good option.

I wouldn't go wider than 275/35 on the 9.5" wheel. Anything wider won't have good side wall support. You may not notice it in daily driving situations but once you push the car it will be less than ideal. Most people running 295's have 10.5" or 11" rear wheels.

[Ashley Schaeffer BMW]

Dont know why everyone is jumping on me for.

He asked what is the MAX tire size for the stock wheels and I think the 295's are the max.

I never said I had the best performance or handling.

[slicer]

Originally Posted by JAM3S

Dont know why everyone is jumping on me for.

He asked what is the MAX tire size for the stock wheels and I think the 295's are the max.

I never said I had the best performance or handling.

Not meaning to "jump on you". You are certainly entitled to your opinion. We are just making the point that some of us, and almost all of the tire manufacturers, think 295's are too wide for a 9.5" rim.

[M3takesNYC]

Originally Posted by slicer

I don't agree with you. My understanding is that wider tires can provide better lateral grip. The shape of the contact patch changes to a more horizontal oval. Why do you think race cars have fender extensions and wide tires front and rear? It's not only for wheel spin reasons. It's for lateral grip. Tires can also adjust certain handling characteristics of the car (just like suspension can). For example - Changing to tire widths in the front that more closely match the rear will reduce under-steer. Making that change is best done with a corresponding adjustment to wheel widths. Did you ever notice that Porsche specs 911's with 295's in the rear and 235's in the front? A base 911 has just over 300 hp. The 295's are not there for wheel spin. They are there because the car is rear weight biased. The extra width adds lateral grip, which helps dial out oversteer - making the car more neutral handling. Again... Wider tires require wider rims to support the width /sidewall. I wouldn't go with super wide tires without adjusting the wheel width.

You can not agree but its physics. Wider tires in and of themselves are not grippier laterally. They are used on race cars because those cars have lightness and engine power which necessitate that wide of a contact patch to allow a slip angle that is reasonable and to prevent wheel spin throughout corners.

You can buy fatter tires and put a bunch of rotating weight and unsprung weight on and go have at it. To each his own!

[slicer]

Originally Posted by M3takesNYC

You can not agree but its physics. Wider tires in and of themselves are not grippier laterally. They are used on race cars because those cars have lightness and engine power which necessitate that wide of a contact patch to allow a slip angle that is reasonable and to prevent wheel spin throughout corners.

You can buy fatter tires and put a bunch of rotating weight and unsprung weight on and go have at it. To each his own!

You should put some 205's on your M3 and go around a corner at speed (keep your foot off the gas to take "wheel spin" out of the equation). Then do the same corner on stock tires.

[M3takesNYC]

205s will break loose and spin and lose traction adn start to slide.

Your car so put the heaviest set you want and enjoy

[slicer]

Originally Posted by M3takesNYC

205s will break loose and spin and lose traction adn start to slide.

Your car so put the heaviest set you want and enjoy

Tires don't spin on corners unless you are putting the power down. They slide.... Take a look at this to help visualize the contact patch change with wider tires.

http://www.tirerack.com/tires/tirete....jsp?techid=10

I'm close to giving up