I make no bones about the fact that I think the wheels look too small. They have increased the size of the car and not the wheels. Even if you lower this car the gap will still be there front and back of the wheel. Most people naturally photograph their New F56's from front and back because those are the best angles but at some angles it does not look so good. The big gap shows off the large overhang too.
So what if you put on 18' rims with 215/45 R18 tires.
Might look good but would give the wheels a bigger diameter. It would likely throw off the speedo and mileage calculations...but there may be a way to adjust those.... They would be quieter and smoother at speed...


Might look mean. Any thoughts??

 

Found this on the Infinity site.

Think the guy is wrong about the speedometer. I would say that at 78mph it will under read at 75mph. Right? He's against it and he brings up a good point about the raising the car 1/2"...not sure you would notice that though..

"I wouldn't recommend changing tire sizes from stock. When you go with a 45 series tire instead of a 40, you will be changing sidewall height and that will change rolling diameter and speedometer accuracy. Although not likely, it is possible that you could have tire rubbing issues @ full lock. To make a long story short, if you have to increase sidewall height for comfort, stick with the 17s.

245/40/18 is the correct size for the 18" factory GS wheel if you want to maintain proper rollout. Going with a 245/45/18 will result in the following....

Approx 1" taller tire
Approx 1/2" increase in ride height.
Approx 3" increase in rollout
At 75mph your speedo will read 78mph assuming it's 100% accurate to begin with
It will also change your overall gear ratio will change performance and gas mileage.

Not a simple change by any means."

 

quieter and smoother at speed? no. not with all things being equal. 18" non run flat vs 17" run flat MAYBE.

 

Relacement tires should have an overall diameter that is within ±3% of the factory specification.

Changing 205/40-18 to 215/45-18 (a 4.5% increase) would be inappropriate. Going with 215/40-18 would be OK.

 

Random. No. 18" with 45's not 40's...be like big 17's right. I never use run-flats.
Not sure you are understanding 17" 45's and 18" 40's are the same sized wheels. 18" give a harder ride because there is less air between the wheel and the rim (less side wall)....But if you have the 18" rims and more sidewall you would get a better (more comfortable ride) and you would have a bigger wheel so it would be smother at speed. The original Mini had small wheels (diameter) and they were pretty noisy as I remember.

 

Miniac. Why is that though? Probably because of the speedo etc...(might be slightly harder on the clutch) ....not for safety or ride quality though. ..?

 

Using figures from Tire Rack on Potenzas, this is what tire sizes ought to do to speeds:

195/55/16 60.3 mph
205/45/17 60 mph
245/40/18 63.4 mph
245/45/18 65.9 mph

If doing a true and indicated 60 mph on 205/45/17s and you switched to the different tire sizes, an indicated 60 would actually be the higher speeds.

 

That's what you need!

 

225 40 18 will likely be the biggest tire size you can use and have clearance IMO.

 

You won't want it to look like a tractor though!

I would say that looking at the stock 205/40 18 tyre size (621mm rolling diameter) you would want either of the following replacements and then combine that with some lowering springs or coilovers to remove the arch gap.

215/35 R18 (608mm rolling diameter which is a -2.09% difference to stock / 13mm smaller)

215/40 R18 - (629mm rolling diameter which is a +1.29% difference to stock / 8mm larger)

That would ensure the wheels did not look lost without having to run oversized rubber which (in my opinion) looks stupid on MINI's

Just my thoughts!

 

ZippyS. That's what I'm talking about!

 

I understand what you're getting at. I don't think I'd run a significantly larger overall tire diameter to minimize the gap you are refering to though. I would use aftermarket suspension and lower it a bit.

 

Although the 20's look too big. It really helps make the car look smaller.
If you lower the car the gap at the front and rear will still be big. In fact it might make the nose look even bigger imo.

 

Yes ... and whatever other tech is based on accurate speed data.

Also, larger diameter tires will accelerate slower than smaller ones.

 

Now I'm thinking 17" 50 215's
Check this out!


http://www.rimsntires.com/specspro.jsp

 

215/50-17 isn't appropriate either ... 4.9% larger than stock.

 

The Hankooks that came with my car are 205/45-17
If I go with 205/50 - 17 they should be fine....right? (11mm all round bigger 2mm wider)

 

If you're concerned about wheel gap you should be considering lowering the car with springs or coilovers.

 

Miniac. Lowering does not solve the problem. The wheels look too small imo. If I lower the car...It will look like a lowered car with small wheels.
I wad just looking at the car 1/2" bigger all round Wil make a huge improvement to the look of the car.
This is only my take on things. When I look at the r56 and r53 the wheels look more proportionate. :-)

 

Lower the car and buy better tires. My Dunlap SP 01 runflats ride better than my prior Bridgestone Potenza non runflats. They handle better too. Summer only. Get winter tires. Bigger tires will probably rub. You won't like that.

 

GregoryK, I have the 18" silver wheels on my black car. It seems like the wheels are all rim and like 1.5" of rubber. They fill out the wheel well pretty good in my opinion. Are your wheels black? I think on the F56, black wheels don't have the same pop as on the R56 because of the larger F56 body proportions. With black wheels, the eyes go to the car body and instead of the wheels. Some 18" JCW F56 wheels may be what you need. They are available now at your dealer. That is my opinion only. That is why they make different options!! Different strokes!

 

champ198. Black 17" with a Grey car....funnily when you use the tool I posted the 18" with the 40's are smaller than the 16 55's.
I'm going to do this as soon as the JCW rims come! I'll post pics...
TBN.. the Hankooks performance summers are pretty dam good. I was so impressed with these new tires I did a posting. I'm going to run Michelin's on the new rims though.

 

Mini of Nashville has a set of 18" JCW 205/40R18 rims/tires 5 bolt F56 wheels by the door to the service dept. I bet your svc dept can hook up the computer and change the wheel size in your ECU to make the speedo read correctly going from 17" to 18".

My GPS and speedo read the same, there is no more 2-3mph difference any more. Just remember that when you're blowing by the Po Po.

 

You better find another tool ...



Putting inappropriately oversized tires on wheels will not make the wheels look bigger.

Your best bet is to fit 18" wheels with 215/40-18 tires.

 

Miniac. Not following your logic mate. Putting slightly bigger ties on the rims will make them look bigger....because they will be bigger. A one 1" taller tire....will be 1" bigger and therefore look bigger.....right? The difference in the roll out speaks to that. The 3mph difference in the speedo could probably be addressed.
As you have demonstrated the outside size of the 18's and 16's are the same so the gap will remain the same = big :-)
17 45's are actually smaller.... .7%