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[Frampton]

I'm ordering the Kumho XS tires this week. I have a short 10 miles twisting hilly drive to work and I will be taking the car to the track every two weeks so Im more interested in traction than noise or treadwear.

I was thinking about running this setup, does anyone else have these tires on stock wheels?

225/40R18 up front
245/35R18 in the rear or 265/35R18?

Can I go larger on the stock 5 stars?

Thanks

[FedeM]

With 265/35 on 8.5" rear stock wheel, u will rub.

[VMRWheels]

Originally Posted by MuCcIo

With 265/35 on 8.5" rear stock wheel, u will rub.

265 is also outside of the recommended width range. 255 would be the max I would safely recommend on a 8.5" wheel.

-Charles@VMRWheels

[dicker]

Originally Posted by maxnix

Why such a cheap downgraded tire on such a well engineered performance car? The tire is the only part of the car that touches the road and hence determines 90% of the dynamic performance envelope.

At least meet or exceed the RE050A specs and quality.

The RE050A is a dog in terms of performance to the kumho XS.

That being said I would not run the 265 rears.

If the car is completely stock the 225 front/245 rear combo should help a bit with the understeer.

[dlong82]

You mentioned tracking the car. Would be nice to know your lap times before and after the change to the XSs.

[Gary@TireRack]

The XS is a great performance tire, especially for dry roads. I agree with not using the 265's on the rear. It does not fit the wheel well and it does rub. 245 would be the better option.

You'll love the increased grip on the twisties!!

[Brian135i]

I'm running the Kumho XS (225/40R18, 245/35R18) right now and they are great for the $$. I wanted to buy the 265's, but the price diff is a lot. WTF?

[Frampton]

thanks for the info guys.

not sure if its necessarily a downgrade because they are less expensive. the guys at the track swear by these tires and tirerack pulled 1.01 g's when put on a stock 3 series. I'll let you know though after I give them a thorough flogging and see what my times look like compared to stock. I'm sure i'll go through enough sets of tires this year to give a healthy comparison to other down the road.

i'll order the 225 245 setup and let you all know what it does for the track.

I did my first track day last weekend at Driveway Austin. Took a level 1 course on the car bone stock with factory bridgestone run flats with about 1/3 tread left. I put in 90+ miles between 9am and 4pm. The L1 course is a pretty technical 0.7 mile with 7 corners.

http://www.drivewayaustin.com/track-maps/short-course

So bone stock and my frist track experience my first run was 43.6 seconds. By the end of the day I was consistently running in the mid 40's. Fastest lap time was a 39.95.

By the end fo the day there was nothing left of the cornering tread on my front right tire and a nearly nothing of the rear tires. Need to put an extra 4-6 psi in the front right tire next time vs the other three on that track. Ran 38-40 psi on the bridgestones.

Bonus and tax returns all hit me at the end of this month so I'll have a few trips to the track in march to test part by part lap times starting with the xs's on stock wheels.

[Frampton]

ordered the tires from tirerack today through my local track, should be in on Monday and will track them next weekend!

Anyone know how many miles I can expect to get on them?

[cpt97m3]

Originally Posted by Frampton

ordered the tires from tirerack today through my local track, should be in on Monday and will track them next weekend!

Anyone know how many miles I can expect to get on them?

I ran through a set of these for street use, and some AutoX. I'm an instructor for the BMWCCA, so I take students for rides. The grip of these is pretty amazing. Don't let the low price fool you. Way better the the 050A runflats I had. I ran 245/35's in back, and would not try a 265 on the OE wheel also.

They do need a little heat in them for best performance though. So not the greatest in real cold weather for the first run. But in So Cal, that's rarely a problem.

I got around 6600 miles on them total, but that included 6 or 7 autox events, so hard to say how long they would last on the street only. They did get a little noisy at the last part of the life. I'm on a set of 225/255 Dunlop Direzza's now.

[Lubo]

Originally Posted by cpt97m3

I ran through a set of these for street use, and some AutoX. I'm an instructor for the BMWCCA, so I take students for rides. The grip of these is pretty amazing. Don't let the low price fool you. Way better the the 050A runflats I had. I ran 245/35's in back, and would not try a 265 on the OE wheel also.

They do need a little heat in them for best performance though. So not the greatest in real cold weather for the first run. But in So Cal, that's rarely a problem.

I got around 6600 miles on them total, but that included 6 or 7 autox events, so hard to say how long they would last on the street only. They did get a little noisy at the last part of the life. I'm on a set of 225/255 Dunlop Direzza's now.

Dunlop's will get noisy as well once they will reach wear bars. They will also tram-line like a bitch. how do the 2 tires compare?

[Lubo]

I have similar story with Michelin, I vouched never to buy them again. To me they are overpriced POS.

[cpt97m3]

Originally Posted by Lubo

Dunlop's will get noisy as well once they will reach wear bars. They will also tram-line like a bitch. how do the 2 tires compare?

I just heard that from someone else about the Dunlops getting noisy also. Too bad. I've only had them for a few days, and so far they are much quieter, and even smoother riding than the Kumho's. But I haven't had a chance to push them hard yet.

[Lubo]

Originally Posted by cpt97m3

I just heard that from someone else about the Dunlops getting noisy also. Too bad. I've only had them for a few days, and so far they are much quieter, and even smoother riding than the Kumho's. But I haven't had a chance to push them hard yet.

Mine's lasted 9k miles. survived at least 80 auto-x runs and 5 HPDE.
They were worn well past their wear bars when thrown out and yes last 2k miles they were louder, but nothing crazy.

[Frampton]

thanks guys, they get installed wednesday after I get the car back from getting the injectors and fuel pump replaced under recall.

forgot to say what i ordered to kill the 265 thread still going.. i got the 245/35's for the rear and 225/40's up front

[Eddy@ApexWheels]

Originally Posted by maxnix

Why such a cheap downgraded tire on such a well engineered performance car? The tire is the only part of the car that touches the road and hence determines 90% of the dynamic performance envelope.

At least meet or exceed the RE050A specs and quality.

The XS is an excellent extreme summer tire. Maybe you're thinking of the older MX which was great for the price, but at that time the RT-615 was better. Times have changed so the new budget tires that are comparable are the Z1, XS, and NT-05.

[Frampton]

Just got back from getting them mounted today and put about 25 miles on them. I ended up with the Kumho XS 245/35/18's in the rear and 225/40/18's up front.

Initial impressions:
The first thing I noticed was that there is a huuuuge difference in comfort level moving from the run flats to the non rft's. It feels a lot smoother over bumps, quieter over normal road surfaces and feels more like a luxury car. I felt like I was driving on rocks with the bridgestone rft's. Steering response is more predictable, you really notice the slow turn in now but it feels pretty good comparatively. The front wheel grip is night and day but I can really feel the road now and the understear is much more noticable. There is a lot more rubber all around just looking at it. They are also a bit taller than the bridgestones and fill the wheel wells better. With traction control off I get a chirp of the tires into second instead of an all out loss of traction like the odl tires. This could be due to having nearly no tread left from a full track day a few weeks ago with the old tires. I'll be hitting the track on Monday and will give a lap time comparision and provide a much better review of the new rubber.


I'll get some pictures after work today and show stance and sideshots and everything.