20" Wheels on 06MY 325i?

Can I put 20" wheels on my 2006 BMW 325i?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Doesn't sound like a good plan. You'll have a VERY tiny sidewall and be prone to jarring and wheel damage. Stick to 18s or 17s.
--
Who needs a life when you've got Unix? :-)
Email: snipped-for-privacy@unixnerd.demon.co.uk, John G.Burns B.Eng, Bonny Scotland
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Assuming you do not cause the overall diameter of the tire to become larger, yes. You need to observe the backspacing, or offset, too.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
This will result in a VERY narrow sidewall.
If you tell us what size tires you have now, I'll calculate what you will end up with if you get 20" rims. Assuming you have either the 225 or 235s now, you will end up with a 25 or 30 sidewall.
The tire has a number, 235/40x17. This means the tire WIDTH is 235mm, the sidewall is 40% of the width, and the rim diameter is 17 inches. The width is a fixed number for the most part. Issues affecting width are the proximity of the shock/springs and the fenders. The diameter is defined by the rims, and the sidewall is a flexible number that causes changes in the gearing - which affects the speedometer and performance, both of these things can be corrected by changing the gear set in the differential.
So, when you change the diameter of the rim, you have to alter the height of the sidewall to maintain the overall diameter so that you do not run into issues with the gearing -- speedometer and performance.
Multiply the width (235) by the sidewall height -- more accurately termed aspect ratio -- (.40) to get one sidewall. Double the number to get the other sidewall. Now, convert the number from millimeters to inches by dividing by 25.4. This will tell you the total sidewall in inches, finally add the rim diameter to determine the overall diameter.
235 x .40 = 94 x 2 = 188 / 25.4 = 7.4 + 17 = 24.4. You currently have a tire that is 24.4 inches in diameter, you want your 20" rims to come out to as close to the same number as possible. If your difference in the new tire is a bit larger, then your speedometer will slow down and you may expose yourself to speeding tickets. If the new tire is a bit smaller, the speedometer will speed up and read a bit faster than you are really going. As a practicle matter, the speedometer reads fast already, and a half inch or so larger tire will make the speedo dead nuts accurate, and you will not get tagged for speeding if yo keep your eye on the instruments.
With the 20s, the 225/25 will be 24.43 inches, the 235/25 will be 24.62. We already figured out that the stock 235/40s are 24.40. So, either of these sizes will fit fine if the only consideration is the gearing. The problem, and this is a huge problem in my mind, is that the 20 inch tires will only give you 2.2 inches between the rim and the pavement. I predict lots of broken rims with this set up. If you currently have the 225/45x17s, then your diameter is 24.9 inches, and the equivelent in a 20 is the 225/30, which gives a bit more protection between your rims and the road -- you get 2.6 inches, which isn't very much.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jeff Strickland wrote:

Long post, yet with nothing mentioning the load capacity of the tire, which is directly related to the tire's cross-sectional area. Such a low-profile tire *cannot* be safe.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'm not prepared to address any of the safety issues related to the extremely low profile. The question was if it was possible. The answer is, yes, but with the qualifications I suggested concerning the resulting sizes.
I do not know that the loading is impossible or not, but I think that I've actually seen packages like the OP is considering. Would I get this package? No. But what drives my decision here isn't the apparent safety issues I overlooked, my decision would be based on the idea that it should look like shit, and not present the image that I want my car to project.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I wouldn't. Your ride will be terrible and I don't think they would look rite. I'd say 18's max for this car.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

You certainly *can*. The question is whether you're stupid and tasteless enough to do it in spite of all advice to the contrary. -- C.R. Krieger (Been there; seen that)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Well...OK...I'd say your choice of words are tasteless, and your overall commentary is quite useless.
But thanks for trying.
E28 Guy wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

I'll just keep it simple. You're an idiot.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

"... choice of words IS tasteless ..."
You're welcome. -- C.R. Krieger (Not illiterate)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

http://www.tirerack.com
--
-Fred W

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.