Im looking at a set of new wheels and the tire sizes are:

FRONT==205X45ZR17
REAR==215X45ZR17

Does it matter that the aspect ratio is larger for two of the tires than the other two?

 

hmm...

1. that might trigger the deflation alert if the circumferance of the two differing sizes is too great

2. i'd really suggest that a square setup is best unless you've some very specialized driving in mind

3. due to the chassis dynamics of the mini, the only non square setups i've heard of put greater width on the front axle, not the rear

4. a non square setup with greater width at the rear will tend to understeer, which the car does anyway out of the box

5. any non square setup will prevent you from doing tire rotation (same side, front to rear) which I find helps tire longevity quite a bit...

would it work? i'd bet it would - the only worry might be the TPMS

anyone out there tried this combo?

 

215/45 will be taller than 205/45, so you'd have an interesting look going there. Any particular reason you're looking into this sort of setup on a FWD car?

http://www.1010tires.com/TireSizeCal...?action=submit

mb

 

Found a used set of wheels that come with those tire sizes. i might ask the seller if he could sell just the wheels seperately.

 

I'm not a tire expert by any means, but that's what I'd recommend, too. I have no clue what would happen with the different widths and height. Best case scenario is you'd just understeer a whole lot more, which isn't necessarily a bad thing from a safety standpoint. But if you're interested in more balanced handling, wider rears is definitely not the way to go.

Good luck!

mb

 

My only experience with different tire sizes f/r is on a R56 at an autocross:
Larger diameter tires on the rear will rotate slower that the fronts, which is exactly the same thing that happens when you are spinning the front tires. DSC would cut power even driving gently at a walking pace from a parking spot thru grid. Once DSC was disabled, no problems :-D

Jason

 

Front an appearance standpoint, it might look kind of cool. Sort of a "raked" throwback if you will. Granted, the cars that used to have some serious rake also usually had glasspacks, air shocks, and broken speakers blaring Dream On but, ya know, whatever floats your boat.

 

For street use-

Don't mix different sizes of tires if your wheels are all the same size-
-i.e. if you have 17x7 all around then choose one tire for everything.

If you have used wheels to buy, get the wheels only so you don't get mixed sizes. Or if one set of tires is really good then take the other tires off and match the size.

Don't mix runflats with non runflats.

All of this is so that your handling is predictable and safe.

The exception is on the track or at autocross when you want to put wider tires on the fronts for more rubber and traction. Not wider on the back, you have a front wheel drive car.

The other exception is when you run wider rims in the rear and you need a wider tire to fit (for appearance mostly) but you will need to closely match tire diameter to get the car to level off.

 

that's priceless! thanks for sharing...

(minihune thank you for saying very directly what i was merely hinting at!)

 

Seller doesnt want to split up the wheels from the tires...damn it!! I think I might still buy the wheels and tires and sell tires on my own...they are Wedssport TC005's in grey.....very hard to find look awesome...

 

How much of a difference in characteristics will there be if I have new 215/45-17 in front and used 205/45-17 rear? I want to keep the Kumho Ecsta SPT's but they are no longer available in 205/45. Tire Rack is not recommending a differnt size and the reason given is that it will affect ABS. If this is true, then what options do I have?

 

In general it depends on how used the tires are and the handling characteristics of your MINI at the present time.

What are your suspension mods?
What year and model MINI?
How do you drive- normal on the street, just like you were on a closed track, or a combination of both?

New tires should always go on the rear axle when one pair is more worn. This is always the case if you care about resisting hydroplaning. The front tires will tend to go where you want and the rear tires will need the extra tread depth to follow in the rain. If you never have any rain then it doesn't matter as much.

Using different sized tires isn't advised. In your case you'd be putting on a taller tire in the front which raises the front and decreases wheel gap, while in the rear you have a stock sized tire with relatively more wheel gap than the front although if you really did do it the gap in the front might already be more than the rear so it might not look terrible.

Different sized tires handle differently as do tires of different makes and models. Mixing tires makes front and rear not handle the same. If you drive only the speed limit then you won't see much trouble but if you push the MINI fast through corners then you could have less than predictable handling.

If all the tires are the same Kumho SPT that helps. Who are you dealing with at tirerack, is it Alex?

Couple of options. Having tires of the same type and all the same size is the goal. You could find another source to match the older tires. You can buy new tires x 4 and sell the older ones as used. You can buy two more tires to match the older size but they would not be Kumho SPT.

ABS is not affected by your tire size if you keep tires all the same size and very close to stock size. ABS works with any wheel tire combo but can be tricked. Depending on what size tire, changing tire size on a car or truck with ABS or traction control can effect the calibration of the speedometer and ABS system so that you my be traveling faster or slower than what the ABS electronics thinks.

Also see this article-
http://www.popularmechanics.com/how_...e/1271776.html
I think the big issue for you is the mixing of different size tires on each axle which is not recommended.

Personally I have run mixed sizes front and rear and many different sized tires (larger and smaller than stock tire diam) on my MINI under controlled performance driving conditions on the track and at autocross for the last 4 years and have never had any issues with ABS not functioning or the ABS light coming on in a way that was unsafe. Handling was OK but I have a fully adjustable suspension that is far from stock settings, this allows much greater use of the full tread of the tires than stock. For the street I always run four identical tires.

 

I too would probably stick w/ same size all around.

I drive a Porsche 930 as my weekend car, it has a different width and height for the front and backs. The backs are large 245's or something like that. ...yet it's also rear wheel drive and needs a lot of rubber in the rear.

In any case, this is my first post, i ordered my Mini w/ 18/205/45 series all black rims.