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      10-06-2010, 10:29 PM   #1
marcw
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New shoes rock!



Finally ditched the runflats today. Even on the short drive home from the tire shop the difference was like night and day. I went with the ever so popular Conti ExtremeContact DWS all seasons in 225/35/19 and 275/30/19. Ride quality has much improved. Going over manhole covers no longer feels like the car is in an earthquake. The tires are very quiet compared to OEM. Steering feels lighter. I'm going on a 300 mile drive on Saturday which gives me plenty of time to break them in.

I can wholeheartedly agree with everybody on the board to ditch the runflats! I should have done this 3900 miles ago. Feels like a completely different car.

-Marc

PS: If anyone is interested in buying my barely used Bridgestones for track tires PM me. I bought a tread depth gauge today so I can measure remaining tread on them.
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      10-06-2010, 10:32 PM   #2
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Quote:
Originally Posted by marcw View Post

PS: If anyone is interested in buying my barely used Bridgestones for track tires PM me. I bought a tread depth gauge today so I can measure remaining tread on them.
You shouldn't have. I could have loaned you mine... Oh well. I sold my remaining front RFTs today!

Congrats on your new tires!
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      10-06-2010, 10:46 PM   #3
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It was less than $5 at Napa. No biggie.
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You shouldn't have. I could have loaned you mine... Oh well. I sold my remaining front RFTs today!

Congrats on your new tires!
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      10-07-2010, 08:22 AM   #4
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marcw,

Happy to hear it, well done! What size did you get?
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      10-07-2010, 08:31 AM   #5
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I am still amazed at the difference. Just wish I had done the 275's. lol
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      10-07-2010, 11:25 AM   #6
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sounds great, cannot wait to ditch the RFT's myself. Guess I am going to go 275 in the rear and 235 in front. I am going with the DW as it is rarely below 45 during the day here in coastal SC in the winter. Thanks silver and others for the input and info.
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      10-07-2010, 11:40 AM   #7
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So, three questions --

1. Which sizes are best?
2. Where to buy? TireRack?
3. Where to sell the RFTs?

Thx!
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      10-07-2010, 12:12 PM   #8
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Quote:
Originally Posted by warden View Post
So, three questions --

1. Which sizes are best?
2. Where to buy? TireRack?
3. Where to sell the RFTs?

Thx!
Need some spoon feeding heh?

1. Depends on your wheel size. Assuming you have 19" wheels I would go 235/35 front 275/30 rear.
2. Anywhere you can find it cheap. Depends on your location. Ebay, Discounttires direct, America's tires are all good choice. Shop around.
3. Anywhere you can: Ebay, Craigslist, E90post, Bimmerfest forums...
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      10-07-2010, 12:20 PM   #9
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Quote:
Originally Posted by warden View Post
So, three questions --

1. Which sizes are best?

For your car I would get thees ..

Click here
.
2. Where to buy? TireRack

Yes order them thru this site here from Tire Rack, when you do this you support this site Click here for the link then fill in your BMW data

3. Where to sell the RFTs?

I would do it on e-bay, provide all the details, some people get them to have available should they need them
Thx!

I added data after your questions ... Good Luck !
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      10-07-2010, 01:38 PM   #10
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Quote:
Originally Posted by Rafale View Post
Need some spoon feeding heh?

Yep, sorry. I promise to reciprocate when I'm less needy.
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      10-07-2010, 01:52 PM   #11
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I wish I had 235's up front. Understeer is definitely noticeable with 225/275 combo. Continental needs to get off their butts and produce some more 235's.
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Originally Posted by Silver-Bolt View Post


I am still amazed at the difference. Just wish I had done the 275's. lol
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      10-07-2010, 01:56 PM   #12
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Quote:
Originally Posted by marcw View Post
I wish I had 235's up front. Understeer is definitely noticeable with 225/275 combo. Continental needs to get off their butts and produce some more 235's.
The 235's won't be much help with understeer. Siffer rear sway bar will cure it.
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      10-07-2010, 02:20 PM   #13
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The 275's do change the look just a bit. No longer looks like an ultra slim tire like the OEM. However, I'm more than willing to compromise on the looks if it saves my rims! The overall sidewall height went from 3 inches (stock) to 3.24 inches. Additional sidewall height was one of the reasons I went with a 275.
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      10-07-2010, 02:38 PM   #14
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Quote:
Originally Posted by warden View Post
2. Where to buy? TireRack?
Thx!
Try this:

* Locate your local Tire Rack installer.
* Ask them if they would match or beat Tire Rack's prices.

It worked for me, I pay the same price as Tire Rack but save on the shipping fees.
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      10-07-2010, 05:47 PM   #15
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as most of you know we went with the Contact DW, 235 front and 275 rear. I took the Tirerack price down to my local Discount Tire store and they matched it; the local option also saved me money because they did not charge me the shipping that Tirerack would have even though they had to order them from a non-local Continental distributor via UPS. it was a great deal and I will never have RFTs on another "sports" car, what a joke - if my wife raves about them over the RFTs you know they are pretty good.

now I have to play with air pressure because I am thinking the RFT recommended pressures in the door sill are too high
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      10-07-2010, 07:46 PM   #16
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why is everyon wanting to get wider tires than the stock ones?
i have the stock 18's so they are 225/40/18 and 255/35/18
what benefit does the wider tire have over the stock size?
any negatives about the wider tires?

thanks.
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      10-07-2010, 08:02 PM   #17
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Two reasons for me. First I think it looks better. Second, the wider rubber can transfer more energy to the street than thinner tires. With the OEM it was pretty easy for me to get the traction control to come on when I really punched it. Less likely to happen with wider tires.
Quote:
Originally Posted by brisk3 View Post
why is everyon wanting to get wider tires than the stock ones?
i have the stock 18's so they are 225/40/18 and 255/35/18
what benefit does the wider tire have over the stock size?
any negatives about the wider tires?

thanks.
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      10-07-2010, 08:26 PM   #18
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Quote:
Originally Posted by marcw View Post
Two reasons for me. First I think it looks better. Second, the wider rubber can transfer more energy to the street than thinner tires. With the OEM it was pretty easy for me to get the traction control to come on when I really punched it. Less likely to happen with wider tires.
Technically, the amount of rubber touching the road is just a function of the weight on the wheel and the tire pressure. With wider tires the shape is wider making the ratio of the wheel touching/not touching the ground smaller. This means better cooling on high speeds, nothing more.

You could lower the air pressure to make the touch area bigger, but that reduces the pressure on the ground and changes nothing either (if the friction would be linear, which I don't know if true in this case).

I agree with your first point, wider tires look better.

Last edited by tot; 10-07-2010 at 09:12 PM..
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      10-07-2010, 09:36 PM   #19
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Quote:
Originally Posted by brisk3 View Post
why is everyon wanting to get wider tires than the stock ones?
i have the stock 18's so they are 225/40/18 and 255/35/18
what benefit does the wider tire have over the stock size?
any negatives about the wider tires?

thanks.
You cannot upsize the rear with the 18" wheels because you are already at the limit in width with the 255. Only the guys with the 19" wheels which are 9" wide can go 275. We can upsize the front tires up to 235 but it would make the front tires larger than the rear in height which would not be especially good. I would have loved to be able to put 275 myself but couldn't so I strongly recommended Marcw to do it.
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      10-07-2010, 11:11 PM   #20
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Thank for the replies.
Guess I will stick with the stock size since I got the 18's.

Thanks!
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      10-08-2010, 08:52 AM   #21
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Quote:
Originally Posted by tot View Post
Technically, the amount of rubber touching the road is just a function of the weight on the wheel and the tire pressure. With wider tires the shape is wider making the ratio of the wheel touching/not touching the ground smaller. This means better cooling on high speeds, nothing more.

You could lower the air pressure to make the touch area bigger, but that reduces the pressure on the ground and changes nothing either (if the friction would be linear, which I don't know if true in this case).

I agree with your first point, wider tires look better.
Way off base here. You can't air down a radial tire to increase the contact patch. Airing down a radial tire causes the center of the tire to cup in toward the wheel and lose contact with the road. Bias-Ply tires you can do that to a point but you will not significantly increase the contact patch. A wider wheel/tire combo will increase the size and shape of the contact patch.
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      10-08-2010, 12:42 PM   #22
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Quote:
Originally Posted by Silver-Bolt View Post
Way off base here. You can't air down a radial tire to increase the contact patch. Airing down a radial tire causes the center of the tire to cup in toward the wheel and lose contact with the road..
True, I was just thinking pressue in general, not actual tyre construction.
Quote:
A wider wheel/tire combo will increase the size and shape of the contact patch.
My point was that the size of the patch is not really depend on the width, but the tyre pressure. The shape changes and generally gives better handling and thus performance.
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