Howdy,

What do you recommend?

205/45/17 or 215/45/17

What differences can I expect between the two on my S-Lites?

 

You'll find more choices with the 215s. The 215s are also slightly taller than the stock 205s and so will slightly hurt acceleration (not that you'll really notice). That same extra height should also yield a slight improvement in ride quality (not that you'll really notice). If you're changing from run-flats you WILL notice a huge improvement.

 

215/40/17 is more proper, keeps the overall diameter so close to the original. If you are interested in droping the car a little, will face rubbing problems on 215/45/17s.

My .02

 

You need to check tire specs guys. Many of the 215s are indeed smaller in diameter/circumference than the 205s - assuming you follow the correct sizing concept; a 205 should be a 45 series tire while a 215 should be a 40 series tire. The 215s also weigh the same in many cases.

There are also rim size ranges for each tire size, but only one ideal in my optinion. A 215 belongs on a 7.5" rim and a 205 on a 7" rim. If you install a 215 on a 7" rim, the tire width will be less than if intalled on a 7.5" rim, and, sidewall strength will be reduced.

Tire side walls must be stretched out a little so stability is enhanced, not the reverse - which will happen if you install too wide a tire on too small a rim. look at tires installed on any F-1 car or any ultra-high performance car.


Go to Tire Rack and check out the SPECS page.

 

I agree with meb. I am running 215/45/17s on Hammans and they are a little too big. I should have gone with 215/40 or 205/45.

 

My current street tires are T1-Rs in 205/45/17 and seem to be a good overall tire for all conditions. I just got a set of Azenis 615s in 215/40/17 for the track but I think the size would be just fine for the street too. My wheels are 45ET so the 215/40s fit with no rubbing even with H-Sport springs so I would think that 215/40 would be just fine on S-lites.

 

By the way, a lot of people don't know this about tires but the second number is NOT a set size like the first but is actually an aspect ratio. This means a 205/45/17 is 205mm wide with a sidewall that is 45% as tall as the width or 92.25mm. A 215/40/17 has an 86mm sidewall and a 215/45 has a 96.75mm sidewall - one is quite smaller and the other is quite larger - neither are ideal.

 

215/40ZR17 = Good 4 me! ... and love every ride on it :smile:


Couldn't afford Harmann wheels like Rick (Anderson) does , so I go with MOMOs ... BTW, nice pix you have at the San Diego British Car Show, Rick

 

Right you are! And as written in my first reply above, the 215/40 has a smaller diameter. As such it will spin 20-30 more revolutions per mile...sounds about right. And so it will accelerate faster too, and have less top end in theory so long as the tire doesn't grow too much. Or, if aero forces are really big, it will become smaller...

It ain't just rubber.

 

Just keep in mind that the math is only one part of the decision. You have to consider what sizes are available, in which tires, and at what price. BTW I'm running 215/45-17 ES-100s on S-Lites with a stock suspension and have had no rubbing issues.

 

There are very few 215/45 options, while a ton of 215/40 options are out there.

Many 215/40's are not rated for the weight of the Mini. And with the shorter sidewall, more susceptible to wheel damage from a good road wallop. Just a cavaet.

With that said, the 40's turn-in faster and rider a bit harder, and you should run more pressure to protect the wheel. I like the 215/40s, handle well and look nice.

 

With 215/40 tires, you'll end up with more miles on the odometer compared to another car with 215/45 tires who went the same distance.

 

I decided on the 215/45/17 BFG g-Force Sport's.

Very nice

 

Why not a 215/40? The 215/45 is taller than you need. If you are concerned with getting all the performance you can, stay with the correct size and select a relatively light tire - 20-22lbs. That tire size is nearly an inch taller

And by the way, I took a look at a number of 215/40s and compared these with the load ratings for 205/45s. They're within 50-125 pounds...between 1,075 - 1,200lbs

 

Those are some awesome looking wheels! - are they the 7 or 8" wide? The problem with the Hammans is that they are 17 x 8 and the offset is not enough to keep them from rubbing. Bad design.

 

Mainly 'cause I found 'em in the 215/45 size, in stock today at a local dealer at a decent price. And I needed a full set of 4 tires ASAP. I think these will work out nicely on this car. Plus, the 45's should ride just a bit smoother than the 40's.

 

Good choice... after going through two sets of Yoko ES100's, I don't miss the tramlining or noise - and the grip level in the dry is pretty much the same from my experience so far!

 

I know you already decided on your tires, but I'm putting this here for other peoples' future reference.

These 215/40-17 Toyo T1-Rs work great for me. They're an 87 load rating, just like the stock 16" runflats, and they're better than the 84 load rating of the 17" runflats, so you don't need to worry about that! They ride better than the 16" runflats (surprisingly), and they handle REALLY well. Also, you don't have to worry as much about rubbing as with the 215/45-17 tires, which are taller than stock.

 

I've run both the 40's and 45's and have uses for each. For the track 205 / 40 Toyo Ra'1's on Ro-Ja 17/7 LT-5's and for the street 215/45 BFG KDW/2 On Hamman 17/8. For the track I like the stick and low sidewall flex of the RA 1's as well as the additional fender well clearence . For the street I like the 215/45 for a better ride , more rim protection , more ground clearance and lastely the better appearance of a fuller wheel well. I also ran some 215/ 40 Bridgstones on the street for a short while. When I was running 40's on the street I found my car bottoming out more on drivewars , speed bumps etc which was funny because with the added gap above the wheel the car appeared to be higher. It was like the worst of both worlds , hit more but looked higher .

Randy
M7 Tuning

 

Ooookay

 

205/45 = 24.2 OD
215/45 = 24.6 OD

As discussed in previos posts load ratings are subjective and vary from manufactures. In that post I explained I calulate load from internal volume. If you run 36 LBS in 215/40 it will meet Mini's GVAW

Alex

 

Also, according to this calculator, the 215/45 is a closer match - whithin 1.43% of the original diameter.

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

mb

btw - love this tire size calculator

 

That calculator is great!

 

DITTO :smile:

 

I wonder if the lord of the board can make the tire size calculator a sticky? This way people have a way to become educated and make their technical decisions on their own, and then if they want subjective feedback they can start a thread. It seems like I've read hundreds of threads on tire size (this is my favorite forum), and most threads leave the seekers of knowledge confused about what is the right size for a car and what people have tried and like. I feel like the calculator can enable people to literally do the math and decide what they want without confusion.

Here is the main page if said lord(s) would like to do that.

http://www.1010tires.com/TireSizeCalculator.asp

mb