Everything You Ever Wanted To Know About Spacers

slimflem wrote

If anyone has 15/12 spacers on a stock E92 with OEM 19" wheels, please post some pics. I'd love to see how this looks. thx.

anthony @ eas wrote

Here's a link to some before and after photos of that exact set-up:
http://www.m3post.com/forums/showpost.php?p=5116979&postcount=6

rzm3 wrote

A great article by TMS... copied from http://www.turnermotorsport.com/html/wheel_spacer_tech.shtml

This is a thread that we've been thinking of for a long time. We also created a page on our website with the same information (more to come!). It consists of everything Turner Motorsport has learned about wheel spacers for BMWs. A lot of this info also applies to other makes as well. It's a very long and comprehensive collection of data, tips, and technical info and it's a bit Turner-centric but should prove useful to everyone. If you should have any further questions, please call or e-mail us.

Why Use Wheel Spacers?

• Appearance. You want to push the wheels out for a better stance and more aggressive look. This is totally subjective to your personal tastes. And we can't tell you what to like...
• Clearance. Many wheels are not compatible with big brake kits. The spoke of the wheel will scrape the new brake caliper and you need a wheel spacer to push the wheel spoke away from the caliper.
• Correction. You may have bought a set of wheels that don't have the correct offset for your car. The offset may be too high, resulting in the wheels sitting too far inward. This is both ugly and incorrect as the tire can now rub on the inside wheel well, or on suspension components, etc. A wheel spacer will push the wheel out and 'correct' the offset.
• Handling. By spacing the wheels further apart, you can make the car more stable and corner better. You can gain a similar effect as adding a wider wheel without the added weight and expense.

Once you know WHY you need spacers, you can figure out what size to use...

tlr wrote

FYI I noticed occasional rubbing with 15mm rear spacers on my E93 + 19" when going over large bumps with 2 or 3 passengers, all EDC settings, top up or down. Front 18mm's seem to be fine so far.

rzm3 wrote

Should be no problem going 15 front, 10 rear based on what others have tried.

Budge wrote

I just got some Vredestein tires in 255/35-19 and 275/35-19 to go with my stock M3 wheels (E90).

I want to get spacers, but my measurements seem wrong. I am measuring 14mm in the front and 17 in the rear. I used the tape and the ruler method and was only 1mm off between the two.

Does that souund right or am I doing this wrong?

I expected to need smaller spacers because each of my tires is 10mm wider than stock. But that doesn't explain why I might need larger spacers in the rear when it seems almost everyone else uses larger spacers in the front.

y2_dyc wrote

budge, did you find out what sizes you needed for yours? i think my e92 may be slightly different to your e90!

aelahi wrote

I own a 2012 E92 M3 with the comp package. I just bought a set of OEM Style 270M wheels for the winter. Do I need spacers? I'm in love with the look and stance of the ZCP wheels and I want to maintain a similar stance with the 270M wheels.

Do these wheels fill the fenders or should I get some spacers?

rzm3 wrote

The 10mm Spacer Dilemma
10mm wheel spacers are one of the most common spacer sizes out there. However, what a lot of people don't realize is that a 10mm size is not a true fitment on any BMW. It's considered a "tuner" fitment, meaning some extra thought is usually required to correctly install them. Only with the right combination of parts will a 10mm spacer fit without a vibration or other fitment issues.

Factory Hub Lips Are Greater Than 10mm
The depth of the lip on the car where the spacer will rest will vary. The available lip space may be 11mm and a 10mm spacer with its own hubcentric lip cannot physically fit. The spacer will bottom out on the lip instead of on the brake hat, leaving a gap between the spacer and the rotor hat. The biggest reason for this is the thickness of the rotor hat. The thickness varies by manufacturer and design. A thinner hat (such as used with aluminum Euro Floating rotors) will leave more lip protruding and make the problem worse. Most spacer manufacturers add an extra chamfer, or shoulder, to push the hubcentric lip further out. The extra chamfer clears any extra part of the stock lip. The other way to get the spacer to fit is to shave the stock lip with a metal file. While not the most elegant solution, it works.

Wheels With Incorrect Beveled Edge
Some wheels (Kosei in particular) have a beveled mounting surface that is at a different angle than on the spacer. Think of really precise puzzle pieces fitting together - if the pieces are not precisely machined to match, the parts don't fit together very well. The wheel will vibrate since enough of the wheel bore is not resting on the spacer lip.

Note that all of this only occurs when using a 10mm spacer with its own hubcentric lip. Any spacer over 10mm is not affected by this. The TMS 10mm spacers with Hub Extender is also exempt from this as the spacer has a flush outer face and will not interfere with the mounting surface of the wheel.

What's the solution? You could shave the stock lip on the car so its depth is under 10mm... Or you could just use a 12mm spacer and be done with it. The difference between a 10mm spacer and a 12mm spacer is the thickness of a nickel! The 2mm difference is smaller than the thickness of a CF memory card or your typical cardboard box. Trust us - 12mm is the way to go. The TMS Hub Extender/10mm Spacer set also works well and allows you to swap spacers in and out for different setups.