So I picked up a set of OEM 17" S-Lites locally because the price was too good to pass up. They have pretty well worn out non RF tires - BFG's in the stock 205-45 size. I installed them today just to get a feel for how the extra weight impacted performance and to get a sense of how much better conventional tires were to the stock run flats.

I have a 08 MCS with the S-winder 16" wheels, which weigh 17.6lbs. The tires are stock sized 195-55 run flats but are mismatched - 3 are GY's and 1 is Kumho and 3 different tread depths.

My first impression with the 17's is the car is more stable and tracks better. Even with totally worn out tires. But at least they are all evenly almost worn out

The car has a bit less torque steer too.

But this combo is overall about 5lbs per wheel heavier, which is adding aprox 10% overall vs. the stock 16" set-up. Which is the wrong direction for peformance.

But maybe for the street this would be an OK set-up. Doesn't seem to handle much differently, and the added grip from normal tires and 205 vs. 195 width probably compensates for the 10% added heft.

I do like the look.

I want to get a set of tires for autox, so if I keep these brick heavy S-Lites for the street, I will likely throw on a set of Hankook Evo V12's in the stock size and then get some autox tires to put on the stock 16" wheels - probably a 225 tire in that case. Car will be in D-stock class or probably class B for BMW club events.

Will I really notice the added heft of these OEM wheels? I could pick up a set of aftermarket 17's for around $500 that would keep the overall tire + wheel weight the same as my OEM 16" set-up, but the added grip of better tires and 10mm wider with shorter section. But is it worth it?

 

Took the car on a favorite section of twisty road near my house this afternoon, and the car has more grip, is more composed, is more predictable with less tq steer than before. So at least as compares to 16's with 195-55 RF's, the 17's with 205-45 conventional tires are a pretty significant improvement, despite the 10 percent added weight per wheel / tire combo. And that's with worn out tires. I'm thinking with fresh rubber the car would rock with these wheels.

Sure - would probably be even better with sub 20lb aftermarket 17's, but saving that expense for now would get me half to 2/3 of the way to a set of R compound 16's to go play with on the autox course.

So I'm leaning towards just keeping them. They do look nice on the car.

 

I just replaced the factory 15 inch wheels with 17" mini lites but went to 205/50/17 Tires because I was hoping for a smoother ride than the standard 45 series. I like the ride and love the look, but since I have a Non-S mini, I really noticed a drop in power and I mean drop; also, I am getting approx 3 to 4 less MPG. I think the Mini lite wheel weights approx 22 lbs each compared to my 15 inch wheels which were around 16 lbs and this does not include the extra weight of the tires.

I do love the look but am contemplating going to wide 16 inch wheels and tires.

 

C4Racer: I think the weight difference between the 16" S-winders (very light for 16" OEM) and the 17" S-Lites (very heavy for 17" OEM) is more like 7.5# each; about 30 more pounds total of unsprung rotating mass. The S probably has enough torque to make that weight gain somewhat less noticeable on an S than SODAA66's total gain of around 24# on a Cooper. Differences in tire weights count too, and the tires are even farther out from the axis of rotation than wheels are.

I've seen all kinds of estimates of how much one pound of unsprung rotating mass is equal to in terms of sprung weight, but my guess is somewhere like 1:4 or 1:5 rather than the 1:20 that one of the NAM advertisers claims. In the latter case, 30# extra in wheels/tires would be equal to adding about 600# of sprung weight; two offensive linemen and a goat as passengers.

Since I already looked these weight ranges up for different sized OEM wheels:
15" = about 12# to 15#.
16" = about 17.5# to 21#.
17" = about 20.5# to 25#.

 

The correct ratio is actually almost a measley 1:2 for the tread of the tire, and about 1:1.7 for sidewalls and about 1:1.5 for the wheels.

 

It does feel like I am carrying around alot of extra weight. I have been using the manual function of the auto trans to make the car go up hills just to get extra zip. If you have to start off from a dead stop to get in front of someone , you need to think twice, until the rpms build up.

 

I went from the S heavies to Enkei RPF1 and the difference in weight was almost 10lbs per wheel. You can definatly feel the weight loss with more tire spin if you are not careful. Acceleration is much better now and it improved gas mileage by about 2mpg.

 

Yes, but the non RF tires are about 2# lighter, so it adds aprox 5lbs which is aprox 13% overall.

I can feel a slight difference in power, but the S makes enough where it doesn't much matter there. And the handling is better with more contact patch, lower sidewall ratio and real performance tires vs. RFT grand tourings. So too many variables there. If I had equal tires but wheels that weighed the same as the OEM 16's I am sure it would be even that much better, because these OEM 17's are so dang heavy.

But it all comes down to how best to allocate limited funds. I want to get tires good for autox. I can spend $1300 or so.

I see 3 options:

1. keep the S-lite-heavy OEM 17's w. Sumitomo HTZ-III tires. 16" R rubber on the OEM S-winders

2. aftermarket 17's w. Dunlop Star Specs

or cheapest option:

3. put Star Specs on the OEM 16's

Still undecided on which path. For now I'm just going to keep driving on the worn out BFG's on these OEM 17's until I decide which way to go.

 

You can easily mount wider than OE size tires on the 16" rims. Size 205/50/16 is a popular switch, even just for road use, and they're even molded for a 6.5" rim, so not a stretch.

How much money you need to spend to be competitive in class probably depends on what you'll be up against where you run.

 

Keep the 17" with decent all season tires for your daily drivers, if you are outside to the snow belt. If you are in the snow belt keep summer tires on the 17" and get some 15x5.5" with real snow tires.

Use the 16" for auto-x with either Dunlop Star Spec, Hankook R-s3, or Falken Azenis RT-615K. Falken offers a 215/45ZR16 that will fit on the stock 16x6.5" rims. They are one heck of a sticky tire, great for wet or dry auto-x or HPDE track days. I've been running the Falkens for the past 6 years and just bought my third set. They are even reasonably priced considering I get three years of hard driving out of a set.

Just my $0.02

 

My experance....
I run x-lite oem 16's summer...lighter gen1 rims, and 15' aftermarket alloys winter...big diff...i initally had the 15's installed on heavy, cheap steel rims, but switched after about 100 miles to light 15's....the car was strightline stable with the heavy rims, but slower to statt turns, and slower off the line...so much so i got the alloy rims, but dgot the return on the steel for nothing, and free mounting...
I can say the lighter rims, using THE SAME EXACT tires made a HUGE DIFFERENCE in the handling and character of my car. Sure they were snow tires, but the only diff was the rims......

 

DS isn't too oversubscribed in my local region SFR Northern CA SF Bay Area. I wouldn't be too far off the pace with a 140 street tire like the star spec on the stock 16 rims. I'm kinda leaning towards that route because it's the lowest cost solution for now and money is tight. Also I'm not really sure how much autox and track days I will get to - some, but not going for the points in autox or anything, just doing it for some fun. I had a road race car and miss the track, so that is my main motivation to get out there again and flog the car and keep my skills up a bit.

Also seems the car will only get 10K miles per year, so might even make it 2 years including track work with those tires on a light car.

 

Depends on your budget and your competition

In D Stock you can run street tires like Dunlop Direzza Star Spec Or Kumho XS which are also fine for street use. They aren't as fast as R compound tires- roughly 1.5+ seconds slower per 40 second run.

Dunlop Direzza Star Spec (Extreme Summer tire)
205/50-16 $147 each, 22 lbs
225/50-16 $148 each, 26 lbs
Kumho Ecsta XS
215/45-16 $114 each, 20 lbs (**great value)
225/50-16 $141 each, 22 lbs

Or you can consider longer wearing and less expensive R compound tires-
these are usually better for track use vs autocross. (softer Kumho V710 and Hoosier A6 are more expensive and wear faster)

BF Goodrich g force R1
225/50-16 fits rims 6-8" wide, $199 each, 21 lbs each
Toyo Proxes R888
195/50-16 $185 each 20 lbs
205/55-16 $202 each, 22 lbs
225/45-16 $205 each, 22 lbs
Toyo Proxes RA1
225/50-16 $207 each, 24 lbs

 

I used to run the R1's back about 15 years ago when I was serious about autoxing. That was before Kumho came out with the V700 and Hoosiers were out and about a half second to a second faster (depending on course length) but wore out at least twice as fast plus cost more up front. I was eying the R1-S if I go with dedicated autox tires.

But may not be worth it since it's still unclear how much I will get out there, and I will also end up doing some track days too.

Otherwise I would just go with the star specs in 205-50-16 on the OEM Winder wheels. Does seem like the 225 is worth an extra 4lbs!! Plus those would be slightly taller than stock increasing the gearing.

 

When selecting tire size you want to match the tire with the wheel width.

A 225mm wide tire will not be as effective unless you have:
A wider than stock wheel with 8" wide as ideal for autocrossing or track
Lots of front negative camber

Still worth considering-
Kumho Ecsta XS
215/45-16 $114 each, 20 lbs (**great value), 23.6" tire diameter is less than stock for lowered gearing good for autocross. Larger tire diameter like 24.9" is not as good for gearing at speeds less than 60 mph.

 

I ran a 255-50-16 on a stock 8" wheel on my Camaro back when I was competing in FS and it worked perfectly. that car was camber challenged in stock form, I could only get about -1 up front.

While the 16x6.5 is not the ideal size for a 225 tire, for autox use it would likely be faster than a 205 tire and 6.5" is the limit for 16" wheels in stock class, so not much can be done about that!

As far as the Kumho's, I do not like the wet performance comments in the car and driver test from Aug. 2009. Diabolical is not a term that is near or dear to my heart describing wet weather performance on a car that my daughter and wife will also be driving!

I think the Star Specs are the winner if I stick with combo street / track tires - I would go with 205-50-16 on the S-winder 16's or the 215-45-17 if I got into a 17x7 aftermarket wheel

 

as a side note - has anyone tried the Hankook Z214 R tires in 205-16 on OEM 16x6.5" wheels for autox?

Looking for any feedback on how well they work, compare to other tires, wear, etc. Price is pretty attractive.

 

The third review on those tires at TR is by the driver of a SMF '06 MCS. He said they're great for the first several heat cycles; can keep up with Hoosiers on concrete but not black top. They tend to overheat, and were toast after 30-40 runs (7 events). I didn't check to see if there were other MINI drivers deeper in the reviews.

 

that's kinda what I figured. Probably better off with the BFG's either R1 or R1-S in terms of getting the most ! for the $ and not giving up too much time on the hoosier crowd. Should be more than fine for regional events, but then again - Star Specs probably would be too....

 

Not so fast, C4. The BFG R1 rates 9th in the TR user survey, whereas the Hankook was 3rd. Maybe someone who's used both will respond.