BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Wheels + Tires Sponsored by The Tire Rack
  TireRack

KEEP M3POST ALIVE BY DOING YOUR TIRERACK SHOPPING FROM THIS BANNER LINK!
View Poll Results: What to do?
Sell both and go for a new set of 19s 10 83.33%
Sell both and go for a new set of 20s 0 0%
Keep the old 20s and sell the 18s 0 0%
Keep the old 18s and sell the 20s 2 16.67%
Voters: 12. You may not vote on this poll

Post Reply
 
Thread Tools Search this Thread
      08-26-2009, 05:10 AM   #1
808E90
808E90
808E90's Avatar
United_States
231
Rep
4,047
Posts

Drives: E90 ///M
Join Date: Aug 2008
Location: Aloha State

iTrader: (21)

Two for One? ... Advice please!

I've been thinking about this for some time now and I still can't make up my mind! Here's the problem ...

I sold my stock 18"s and got two new sets of wheels: 20" Advan RS-Ds and 18" Advan RG-IIs. When I first bought them I was thinking I could use the 18" as a back up or track set and the 20" as my everyday set. I’ve been so busy at home with our newborn that I really don’t see myself going to the small track that we have. The 18s also makes the car sit low and I go places with huge dips. The ride on the 20s is kinda harsh on our Hawaii roads and I'm just not to happy with the look.

I am now thinking of selling the two and getting one nice set of 19” wheels. I would have the comfort, performance and I could really use the space that the second sets take up too. I was looking into some BBS LM-Rs but the 19" wheels look so small on the E90!

Here link to a few pics of both wheels:
http://www.m3post.com/forums/showthr...&highlight=JDM


Thanks!
Appreciate 0
      08-26-2009, 05:25 AM   #2
skierman64
Brigadier General
skierman64's Avatar
United_States
125
Rep
3,071
Posts

Drives: E92M3-E46M3-E46Wagon-E89Z4-E36
Join Date: Dec 2006
Location: Greater St Louis Metro area

iTrader: (1)

Garage List
1994 325is Race Car  [0.00]
2011 BMW Z4  [0.00]
1998 M3 Coupe  [0.00]
2008 M3 Coupe  [0.00]
It seems strange that the 18s would make the car sit lower. The outside diameter of the tire should be the same regardless of the wheel size. For example the 18s should have more tire sidewall to make up for the smaller wheel diameter. Are you running stock sizes on the 18s?
__________________
Invest Wisely...The best mod for your money?? BMWCCA high performance driver's school. The mod that lasts a lifetime and improves the performance of any car you drive[/LEFT]
Appreciate 0
      08-26-2009, 06:29 AM   #3
Lemans_Blue_M
Automotive Industry Insider
Lemans_Blue_M's Avatar
United_States
462
Rep
1,948
Posts

Drives: Lemans Blue M3
Join Date: Aug 2007
Location: Texas

iTrader: (0)

Sell both of your current sets and get the OEM 19's plus a few other mods.
__________________
The best is yet to come...
Appreciate 0
      08-26-2009, 06:33 AM   #4
drivendriver
Second Lieutenant
drivendriver's Avatar
5
Rep
269
Posts

Drives: 2010 E83 X3
Join Date: Apr 2009
Location: Alexandria, VA

iTrader: (0)

Quote:
Originally Posted by skierman64 View Post
It seems strange that the 18s would make the car sit lower. The outside diameter of the tire should be the same regardless of the wheel size. For example the 18s should have more tire sidewall to make up for the smaller wheel diameter. Are you running stock sizes on the 18s?
Just what I was thinking and wondering.
Appreciate 0
      08-26-2009, 01:08 PM   #5
808E90
808E90
808E90's Avatar
United_States
231
Rep
4,047
Posts

Drives: E90 ///M
Join Date: Aug 2008
Location: Aloha State

iTrader: (21)

Quote:
Originally Posted by skierman64 View Post
It seems strange that the 18s would make the car sit lower. The outside diameter of the tire should be the same regardless of the wheel size. For example the 18s should have more tire sidewall to make up for the smaller wheel diameter. Are you running stock sizes on the 18s?
Quote:
Originally Posted by drivendriver View Post
Just what I was thinking and wondering.
Sorry ... I meant that it sits lower then the 20s
Appreciate 0
      08-26-2009, 08:36 PM   #6
skierman64
Brigadier General
skierman64's Avatar
United_States
125
Rep
3,071
Posts

Drives: E92M3-E46M3-E46Wagon-E89Z4-E36
Join Date: Dec 2006
Location: Greater St Louis Metro area

iTrader: (1)

Garage List
1994 325is Race Car  [0.00]
2011 BMW Z4  [0.00]
1998 M3 Coupe  [0.00]
2008 M3 Coupe  [0.00]
Quote:
Originally Posted by 808E90 View Post
Sorry ... I meant that it sits lower then the 20s
There shouldn't be a difference between 18s, 19s, and 20s on ride height assuming the proper size tires are being used.
__________________
Invest Wisely...The best mod for your money?? BMWCCA high performance driver's school. The mod that lasts a lifetime and improves the performance of any car you drive[/LEFT]
Appreciate 0
      08-26-2009, 08:47 PM   #7
isugoo
Major General
isugoo's Avatar
United_States
247
Rep
6,125
Posts

Drives: 991.2 GTS
Join Date: Feb 2008
Location: Irvine, CA

iTrader: (73)

Quote:
Originally Posted by skierman64 View Post
There shouldn't be a difference between 18s, 19s, and 20s on ride height assuming the proper size tires are being used.
Most of 20 tire setups have bigger overall diameter.
I think because most of 20" wheels for M3 application are 9-9.5F and 10-11R. So people tend to go with 255/30, 285/30 (245/30F, 265/30R will be pretty stretch look) and those setups have bigger overall diameters than our stock 18/19 tire diameters.
__________________

PAST: F80 M3 ZCP | 911.1 C2S | F10 M5 ZCP | E70 X5M | E90 M3 | E46 M3 | E36 M3
Appreciate 0
      08-26-2009, 08:59 PM   #8
Lemans_Blue_M
Automotive Industry Insider
Lemans_Blue_M's Avatar
United_States
462
Rep
1,948
Posts

Drives: Lemans Blue M3
Join Date: Aug 2007
Location: Texas

iTrader: (0)

Quote:
Originally Posted by skierman64 View Post
There shouldn't be a difference between 18s, 19s, and 20s on ride height assuming the proper size tires are being used.
Your right, there shouldn't be a difference if the tire dimensions stay the same. (regardless of the wheel diameter)

BUT, here's the problem...

There are 'fitment gaps' in the tire sizing charts between 18", 19" and 20" tires. It's impossible to line these tire dimensions up perfectly, as you increase wheel diameters and widths beyond the stock OE sizes.

Everything gets out of wack, and you end up somewhere in between two tire sizes that you don't really want. At that point, you have to choose the more aggressive tire size (which may rub), or the more conservative tire size (which will transmit more NHV to the cabin).

And to make matters worse...the tire with the exact dimensions you want...is simply too wide (or narrow) for the wheel you bought.
__________________
The best is yet to come...
Appreciate 0
      08-28-2009, 04:49 PM   #9
ben@tirerack
M3Post Supporting Vendor
87
Rep
964
Posts

Drives: 740i
Join Date: Mar 2008
Location: South Bend, IN

iTrader: (0)

That pretty much sums it up right there, especially when you have to consider staggered front/rear sizes. Maintaining front to rear proportionality adds yet another headache.

255/30R20 and 275/30R20 are a little wider, not too much taller, and will not rub (assuming wheel offsets are reasonable). Max wheel widths would be 9.5 Front and 10 rear.
__________________
_______________________________________________
I have accepted a new position at Tire Rack and am no longer in the sales department. gary@tirerack.com is available to assist with M3 questions.
Appreciate 0
      08-29-2009, 01:32 PM   #10
MTROIS
Major
MTROIS's Avatar
France
188
Rep
1,153
Posts

Drives: on the wrong side of the Ocean
Join Date: Jul 2008
Location: New Jersey, USA

iTrader: (0)

Given the roads on which you drive... keep your 18"s!! They have more side walls and you will have a lower chance of bending them + quality of the ride + cheaper tires available + more choices for track tires available = more comfort and money in your pocket...
__________________
2019 M2C MT (ED + PCD) | 2008 M3 Coupé MT | 1995 M3 LTW MT | BMW CCA HPDE Instructor
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 12:53 PM.




m3post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST