E90Post
 


Lux Angel Eyes
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > All-Wheel-Drive (Xi / xDrive) Talk > Wheel gap reduction--without lowering?



Reply
 
Thread Tools Search this Thread
      10-11-2009, 04:22 AM   #1
Dereleek
Second Lieutenant
7
Rep
233
Posts

 
Drives: 2009 E92 M3
Join Date: Sep 2009
Location: Centennial, CO.

iTrader: (1)

Wheel gap reduction--without lowering?

I know this has been covered before, but I don't see why this wouldn't work.
As with most xdrive owners that have stock suspension, I can fit four fingers in the gap from the top of the tire to the fender. My car currently has 225/45/17s (63.43 centimeter diameter) all around. I want to upgrade the wheels to 19s, but also increase the diameter in order to fill some of the wheel gap without lowering.

This would mean picking a higher profile tire for the new wheels, but still maintaining 1% or less for the rolling diameter. With the setup of 235/45/19 (69.41 centimeter diameter) front and 265/40/19 rear the front wheel gap alone would be reduced by 2.4 inches (6 centimeter increase in diameter over stock). This combination also allows the rolling diameter to be 0.1%

Why wouldn't this work? Am I missing something? That seems like a major decrease in wheel gap without having to drop. I don't think that the 2.4 inch increased diameter in the rear would cause it to rub.

Any thoughts?
__________________
2009 E92 M3 6MT/AW/Black Extended/Premium/Tech/Enhanced audio/19" 220m MODs:AC Schnitzer CF rear diffuser/Vorsteiner CF front lip/OEM CF rear spoiler/Vorsteiner full interior CF trim/Eisenmann sport exhaust/Active Autowerke/Angel Eyes
Appreciate 0
      10-11-2009, 04:27 AM   #2
Dereleek
Second Lieutenant
7
Rep
233
Posts

 
Drives: 2009 E92 M3
Join Date: Sep 2009
Location: Centennial, CO.

iTrader: (1)

No 265/40/19 tires

Quote:
Originally Posted by derek0812 View Post
I know this has been covered before, but I don't see why this wouldn't work.
As with most xdrive owners that have stock suspension, I can fit four fingers in the gap from the top of the tire to the fender. My car currently has 225/45/17s (63.43 centimeter diameter) all around. I want to upgrade the wheels to 19s, but also increase the diameter in order to fill some of the wheel gap without lowering.

This would mean picking a higher profile tire for the new wheels, but still maintaining 1% or less for the rolling diameter. With the setup of 235/45/19 (69.41 centimeter diameter) front and 265/40/19 rear the front wheel gap alone would be reduced by 2.4 inches (6 centimeter increase in diameter over stock). This combination also allows the rolling diameter to be 0.1%

Why wouldn't this work? Am I missing something? That seems like a major decrease in wheel gap without having to drop. I don't think that the 2.4 inch increased diameter in the rear would cause it to rub.

Any thoughts?
Right after I typed the post above, I check tirerack.com and they don't carry 265/40/19 tires. DAMN!!!!
__________________
2009 E92 M3 6MT/AW/Black Extended/Premium/Tech/Enhanced audio/19" 220m MODs:AC Schnitzer CF rear diffuser/Vorsteiner CF front lip/OEM CF rear spoiler/Vorsteiner full interior CF trim/Eisenmann sport exhaust/Active Autowerke/Angel Eyes
Appreciate 0
      10-11-2009, 09:21 AM   #3
cb1111
I ask the questions you're afraid to ask.
cb1111's Avatar
27
Rep
2,489
Posts

 
Drives: 335xi
Join Date: Sep 2009
Location: DC

iTrader: (2)

Not a good idea.

Your speedometer and odometer will be off by over 8% and the dealership will - correctly - deny warranty service on suspension and drivetrain bits.

On second thought, the dealer may deny any warranty service because of the odometer issue.
Appreciate 0
      10-12-2009, 09:03 AM   #4
MassBimmer
Major General
MassBimmer's Avatar
77
Rep
7,041
Posts

 
Drives: E90 LCI 328i xDrive
Join Date: May 2009
Location: Norfolk, MA

iTrader: (6)

Garage List
2009 BMW  [4.50]
Yeah, bad idea man..
__________________
E90 LCI 328i xDrive: M-Sport Conversion / BMW Performance Exhaust / BMW Performance Intake / BMW Performance Steering Wheel / VMR V710 / KW V1
Appreciate 0
      10-13-2009, 11:27 AM   #5
Dereleek
Second Lieutenant
7
Rep
233
Posts

 
Drives: 2009 E92 M3
Join Date: Sep 2009
Location: Centennial, CO.

iTrader: (1)

How do you figure?

Quote:
Originally Posted by cb1111 View Post
Not a good idea.

Your speedometer and odometer will be off by over 8% and the dealership will - correctly - deny warranty service on suspension and drivetrain bits.

On second thought, the dealer may deny any warranty service because of the odometer issue.
What calculation are you using? Here is an example: Running 235 45 18s up front and 265 40 18s rear there is only 0.1% difference in the speedometer based on the calculated rolling radius. That is almost perfect, although it isn't what BMW would recommend. This setup would also take 1.4 inches from the front wheel gap.
__________________
2009 E92 M3 6MT/AW/Black Extended/Premium/Tech/Enhanced audio/19" 220m MODs:AC Schnitzer CF rear diffuser/Vorsteiner CF front lip/OEM CF rear spoiler/Vorsteiner full interior CF trim/Eisenmann sport exhaust/Active Autowerke/Angel Eyes
Appreciate 0
      10-13-2009, 01:08 PM   #6
Lexor1704
Bimmer Fanatic
Lexor1704's Avatar
0
Rep
42
Posts

 
Drives: 2008 335xi, Spark Graph, Lemon
Join Date: Nov 2007
Location: Madison WI

iTrader: (0)

Tires that much larger than stock are not a good idea for numerous reasons. I would also suggest getting the car checked out as a 4 finger gap would be 3 inches by my hand and is twice the gap of my stock car. I realize it is more than the stock RWD by a MASSIVE 1/2 inch but let's not make it seem like a SUV.

In all seriousness do a suspension change if the gap is not to your liking. Not only will it fix the visual but it will make the car more fun to drive.
__________________
2008 335xi | E90 | Spark Graph | Lemon | Poplar | ZPP | ZSP | Navi | CWP | 18" | HD Radio | CA | 6FL
Appreciate 0
      10-13-2009, 01:48 PM   #7
cb1111
I ask the questions you're afraid to ask.
cb1111's Avatar
27
Rep
2,489
Posts

 
Drives: 335xi
Join Date: Sep 2009
Location: DC

iTrader: (2)

Quote:
Originally Posted by derek0812 View Post
What calculation are you using? Here is an example: Running 235 45 18s up front and 265 40 18s rear there is only 0.1% difference in the speedometer based on the calculated rolling radius. That is almost perfect, although it isn't what BMW would recommend. This setup would also take 1.4 inches from the front wheel gap.

Simple - go to the wheel and tire forum and plug in your two tire sizes. BTW, in your first post you talked about going to a 265/40/19 tire. That would result in a 8.6% difference from stock.

If the size difference is minimal, then why do you think that wheel gap would be reduced?

Please re-read your original post and plug the numbers into the calculator.
Appreciate 0
      10-13-2009, 02:01 PM   #8
Dereleek
Second Lieutenant
7
Rep
233
Posts

 
Drives: 2009 E92 M3
Join Date: Sep 2009
Location: Centennial, CO.

iTrader: (1)

Quote:
Originally Posted by cb1111 View Post
Simple - go to the wheel and tire forum and plug in your two tire sizes. BTW, in your first post you talked about going to a 265/40/19 tire. That would result in a 8.6% difference from stock.

If the size difference is minimal, then why do you think that wheel gap would be reduced?

Please re-read your original post and plug the numbers into the calculator.
I used the calculator to get those numbers. You can only take the difference the 8% difference from stock into account as detrimental if I went 265 45 19 all around, which would be stupid. Instead, like I said in my original post, I was suggesting going 225/45/19 front and 265/40/19 rear. Now the wheels and tires are staggered and would mean the rolling diameter is very similar 0.1% between the four of them Isn't this the same in principle as what other XI owner do when they go staggered and commonly go 235/35/19 front and 275/30/19 rear, which amounts to around 0.2% difference between the four.
__________________
2009 E92 M3 6MT/AW/Black Extended/Premium/Tech/Enhanced audio/19" 220m MODs:AC Schnitzer CF rear diffuser/Vorsteiner CF front lip/OEM CF rear spoiler/Vorsteiner full interior CF trim/Eisenmann sport exhaust/Active Autowerke/Angel Eyes

Last edited by Dereleek; 10-13-2009 at 02:02 PM. Reason: Left out information
Appreciate 0
      10-14-2009, 11:49 PM   #9
UdubBadger
Banned
No_Country
348
Rep
24,716
Posts

 
Drives: '04 330i ZHP
Join Date: Dec 2007
Location: Chicago Burbs

iTrader: (22)

Garage List
2004 BMW 330i ZHP  [4.75]
2011 135i  [3.73]
2008 328xi  [4.38]
not going to work, you seem to not realize that the more rubber you add to the top to close the gap, the more rubber will be on the bottom between the rim and the road.

you're GAP will not decrease without shorter springs. Your ride height (ground clearance) will also skyrocket and make the car handle like shit.
Appreciate 0
      10-15-2009, 01:17 AM   #10
TWiTCHY
Lieutenant Colonel
TWiTCHY's Avatar
United_States
35
Rep
1,762
Posts

 
Drives: '13 X3 35i
Join Date: Jul 2008
Location: Bellevue, WA

iTrader: (0)

Quote:
Originally Posted by UdubBadger View Post
not going to work, you seem to not realize that the more rubber you add to the top to close the gap, the more rubber will be on the bottom
I'm sorry but

Well said.
Appreciate 0
      10-15-2009, 10:14 AM   #11
ceb
NHTSA Nazi
21
Rep
1,979
Posts

 
Drives: 335ix
Join Date: Aug 2009
Location: MD

iTrader: (1)

Quote:
Originally Posted by derek0812 View Post
I used the calculator to get those numbers. You can only take the difference the 8% difference from stock into account as detrimental if I went 265 45 19 all around, which would be stupid. Instead, like I said in my original post, I was suggesting going 225/45/19 front and 265/40/19 rear. Now the wheels and tires are staggered and would mean the rolling diameter is very similar 0.1% between the four of them Isn't this the same in principle as what other XI owner do when they go staggered and commonly go 235/35/19 front and 275/30/19 rear, which amounts to around 0.2% difference between the four.
Keeping the rolling diameter between the four wheels is one thing, but you want to increase the diameter of all 4 by over two inches. Half of that is going to slightly close your gap while the other half will raise your car. The increased diameter will screw up your speedometer and odometer readings that will cause the dealer to refuse service.

I know you want to "mind the gap" but this isn't the way to do it.
Appreciate 0
      10-15-2009, 11:01 AM   #12
FastLane
Live life in this lane....
FastLane's Avatar
7
Rep
327
Posts

 
Drives: E92 335xi
Join Date: Jan 2008
Location: Chi-Town, USA

iTrader: (0)

Just stack as many obese people as you can into the vehicle, one in the trunk, and you are all set!
__________________
'08 E92 335xi: the girlfriend
'04 Yamaha R6: the mistress
'99 Mustang Cobra: the wife
Appreciate 0
      10-15-2009, 01:09 PM   #13
Nikolas
Colonel
20
Rep
2,068
Posts

 
Drives: 996 TT
Join Date: Jul 2007
Location: Sierra Mountains

iTrader: (0)

Quote:
Originally Posted by UdubBadger View Post
not going to work, you seem to not realize that the more rubber you add to the top to close the gap, the more rubber will be on the bottom between the rim and the road.

you're GAP will not decrease without shorter springs. Your ride height (ground clearance) will also skyrocket and make the car handle like shit.
It would still make the gap smaller between the fender. The hub is a fixed point. Expanding the diameter will decrease the fender gap along with a slighter increase in ride height (smaller due to compression of the tire due to weight.)

Personally I don't think doing what the OP is proposing will do anything bad mechanically and it may just set the speedo at a more accurate speed. Currently they read high as it is.
Appreciate 0
      10-15-2009, 01:26 PM   #14
UdubBadger
Banned
No_Country
348
Rep
24,716
Posts

 
Drives: '04 330i ZHP
Join Date: Dec 2007
Location: Chicago Burbs

iTrader: (22)

Garage List
2004 BMW 330i ZHP  [4.75]
2011 135i  [3.73]
2008 328xi  [4.38]
forget it...

now I'm fucking confused
Appreciate 0
      10-15-2009, 02:06 PM   #15
F104
Captain
Belgium
8
Rep
727
Posts

 
Drives: E92 320D M-sport
Join Date: Apr 2008
Location: belgium

iTrader: (0)

Quote:
Originally Posted by Nikolas View Post
It would still make the gap smaller between the fender. The hub is a fixed point. Expanding the diameter will decrease the fender gap along with a slighter increase in ride height (smaller due to compression of the tire due to weight.)

Personally I don't think doing what the OP is proposing will do anything bad mechanically and it may just set the speedo at a more accurate speed. Currently they read high as it is.
+1
I'm looking around for one size larger now the RFT's are almost gone. On the rear i have 255, so one size larger is pretty exactly one more 1" in diameter. With M suspension it is lowered 20mm, so i would loose 12mm of the lowering. Yes affects speedo readings by 4% or so, but the thing is off by much more than that anyway on even brandnew tyres.
Someone in Germany did it with TUV approval - can't find the posting
Appreciate 0
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
Forum Jump


All times are GMT -5. The time now is 09:00 AM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
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