E46 M3 Wheel & Tire Fitment Guide

ARC-8 // Front: 18x8.5" ET38 with  225/40-18 // Rear: 18x9.5" ET22 with 255/35-18

Recommended for: Those who want a bolt-on fitment that will not require additional modifications and is very unlikely to rub the fender liners, suspension components, etc. You'll gain some performance as well resulting from the wheels being lighter than stock, and the tires being slightly wider. These setups offer an improved stance, but not enough to require rolled fenders, compromises on tire size, or negative camber adjustments. These setups can be used for the occasional autoX and/or track day, but they won’t maximize performance as you'll be leaving a bit of wheel and tire width on the table for the sake of having an easy direct fitment.

Additional Factors: The following items should be considered when choosing a fitment from this category.

• Square vs. Staggered
• Wheel Diameter
• Brake Clearance (if using aftermarket big brake kit)

Tire Selection: Any all-season or Performance Summer tires will work great with these fitments. Our choice would be the Michelin Pilot Sport A/S 3+ if you drive in near or below-freezing temperatures, or the Pilot Sport 4S for warmer climates.

 

Our Recommendations

The Bolt-On Square Fitment
An 18" bolt-on rotatable fitment suitable for occasional track or autocross events, without requiring additional suspension or fender modifications. The most affordable setup where tires can be rotated front-to-rear and no additional modifications are required to make the wheels fit.

• Front & Rear: 18x9” ET30 (or ET31 depending on design) with 255/35-18 tires 
  
  • Direct fit.
  • With certain tire brands and low ride heights, front fender liner rubbing may occur.
  • Rear 12mm spacers recommended for aesthetics. The effective rear offset of ET18 or ET19 gives you the look of a more flush staggered fitment while retaining the ability to rotate tires front-to-rear.
    
    

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The Bolt-On Staggered Fitment
An 18" bolt-on staggered fitment with a slight increase in wheel & tire width compared to stock. Factory handling characteristics will be retained. This 18" setup will weigh less and tires will be less expensive than the 19" version below.

• Front: 18x8.5 ET35 (or ET38 depending on design) with 235/40-18 tires
  Rear: 18x9.5” ET22 with 265/35-18 tires
  
  • Direct fit.
  • OEM 225/45-18 and 255/40-18 tires can also be used.
  • Wider 245/40-18 front and 275/35-18 rear tires can also be used as a direct fit.
    
    

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The Essence of OEM+
A 19" version of the bolt-on staggered fitment, with only a slight increase in wheel & tire width compared to stock. A clean and plausibly-factory look with significant weight savings compared to stock.

• Front: 19x8.5” ET35 with 235/35-19 tires
  Rear: 19x9.5” ET22 with 265/30-19 tires
  
  • Direct fit.
  • OEM 225/40-19 and 255/35-19 tires can also be used.

 

ARC-8 // Front: 18x9.5" ET35 with 245/40-18 // Rear: 18x10.5" ET27 with 275/35-18

Recommended for: Enthusiasts looking for a much wider and more aggressive stance than stock. We only list staggered wheel and tire configurations within this category to ensure front and rear wheel widths and offsets are optimized for the respective front and rear fender arches. These setups aim for a perfectly flush fitment with the fender arch, not recessed, and not poking beyond the body. While many of these fitments can be achieved without any modifications, there are variables at play like vehicle ride height, suspension type, and tire size/brand which may require additional work to prevent rubbing. 

Additional Factors: The following items should be considered when choosing a fitment from this category.

• Square vs. Staggered
• How to Prevent Rubbing
• Will Your Suspension Clear?
• Will You Need Negative Camber?
• Wheel Diameter
• Brake Clearance (if using aftermarket big brake kit)

Tire Selection: Any all-season or Performance Summer tires will work great with these fitments. Our choice would be the Michelin Pilot Sport A/S 3+ if you drive in near or below-freezing temperatures, or the Pilot Sport 4S for warmer climates.

 

Our Recommendations

The Aggressive 18" Bolt-On Wheel Package
The most aggressive bolt-on 18"  setup without the possibility of needing spacers with nearly all aftermarket and OEM setups. Wheels and tires will be an inch wider than the OEM setup, but they don't require any extra work to prevent rubbing.

• Front: 18x9” ET30 or ET31 (EC-7) with 245/40-18 tires
  Rear: 18x10” ET25 with 275/35-18 tires
  • Direct fit.
  • With certain tire brands and low ride heights, front fender liner rubbing may occur.
    
    

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The More Aggressive 18" Wheel Package
Go wider with 18s. Perfectly flush with minimal modifications. This fitment maximizes wheel width using all available space within the fenders. Tires will appear ever-so-slightly stretched in order to clear the fenders.

• Front: 18x9.5” ET35 with 245/40-18 tires
  Rear: 18x10.5” ET22 (or ET27 depending on design) with 275/35-18 tires
  • Available in all APEX designs. 
  • Front 5mm or larger spacers required with certain aftermarket suspensions. When spacers are added, front negative camber may be required.
  • Rear negative camber and/or rolled fenders may be required.
  • Tires will appear slightly stretched (see above photo).
  • 265/35-18 front and 285/35-18 rear tires may work with additional negative camber.
  • With certain tire brands and low ride heights, fender liner rubbing may occur.
    
    

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The Spacer-Free Aggressive 18" Wheel Package
Go wider with 18s, spacer-free. Same as the fitment above but uses a lower front offset to avoid the spacer requirement that may be necessary with certain suspensions. As a result, more front negative camber will be required to prevent rubbing.

• Front: 18x9.5” ET22 with 245/40-18 tires
  Rear: 18x10.5” ET22 with 275/35-18 tires.
  • Available in all APEX designs.  
  • At least -2.0º of front negative camber required.
  • Rear negative camber and/or rolled fenders may be required.
  • Tires will appear slightly stretched (see above photo).
  • 265/35-18 front and 285/35-18 rear tires may work with additional negative camber.
  • With certain tire brands and low ride heights, fender liner rubbing may occur.
    
    

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The Aggressive 19" Bolt-On Wheel Package
The most aggressive and functional 19" bolt-on setup without the possibility of needing spacers with nearly all aftermarket and OEM setups. Wheels and tires will be an inch wider than the OEM setup, but they don't require any extra work to prevent rubbing.

• Front: 19x9” ET28 (ARC-8) or ET30 (EC-7 & SM-10) with 245/35-19 tires
  Rear: 19x10” ET25 with 275/30-19 tires
  
  • With certain tire brands and low ride heights, fender liner rubbing may occur. 
    
    

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The More Aggressive 19" Wheel Package
Go wider with 19s. Perfectly flush with minimal modifications. This fitment maximizes wheel width using all available space within the fenders. Tires will appear ever-so-slightly stretched in order to clear the fenders.

• Front: 19x9.5” ET33 with 245/35-19 tires
  Rear: 19x10.5” ET22 with 275/30-19 tires 
  • Available in our ARC-8, EC-7, and SM-10 designs. 
  • Front 5mm or larger spacers required with certain aftermarket suspensions. When spacers are added, front negative camber may be required.
  • Rear negative camber and/or rolled fenders may be required.
  • 265/30-19 front tires may work with additional negative camber.
  • 285/30-19 rear tires can also be used.
  • With certain tire brands and low ride heights, fender liner rubbing may occur.
    
    

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The Spacer-Free Aggressive 19" Wheel Package
Go wider with 19s, spacer-free. Same as the fitment above but uses a lower front offset to avoid the spacer requirement that may be necessary with certain suspensions. As a result, more front negative camber will be required to prevent rubbing.

• Front: 19x9.5” ET22 with 245/35-19 tires
  Rear: 19x10.5” ET22 with 275/30-19 tires 
  
  • At least -2.0º of front negative camber required.
  • Rear negative camber and/or rolled fenders may be required.
  • 265/30-19 front tires may work with additional negative camber.
  • 285/30-19 rear tires can also be used.
  • With certain tire brands and low ride heights, fender liner rubbing may occur.

 

EC-7 // Front & Rear: 18x9.5" ET35 with 265/35-18

Recommended for: These “dual-duty” fitments are recommended for enthusiasts focused on maximizing performance, whether you use your car primarily on the street, or you’re a weekend warrior attending autoX and/or track days. This category includes both staggered and square configurations to best suit each individual drivers priorities, goals and preferences for their vehicle. While many of these fitments can be achieved without any modifications, there are variables at play like vehicle ride height, suspension type, and tire size/brand which may require additional work to prevent rubbing. 

Drivers going this route should be open to modifications like dialing in negative camber and/or lightly rolling the rear fenders to prevent/minimize rubbing. Even if your wheel and tire configuration does not require negative camber to fit under the fender arches, we highly suggest dialing in negative camber to maximize grip throughout the corners, and to improve turn-in. Negative camber will also ensure you are leveraging your extreme summer or R-compound tires to their fullest potential, and will dramatically extend the life of your tires. Read our article to learn more about The Positives of Negative Camber. Note: 19" wheels aren't recommended in this section. Performance dictates that the smallest possible wheel diameter be used that clears the brakes. We aren't aware of any reasonably performance-oriented E46 M3 brake setups that require 19" wheels.

Additional Factors: The following items should be considered when choosing a fitment from this category.

• Square vs. Staggered
• How to Prevent Rubbing
• Will Your Suspension Clear?
• Will You Need Negative Camber?
• Wheel Diameter
• Brake Clearance (if using aftermarket big brake kit)

Recommended Tires: Any Ultra High Performance, Max Performance, or Extreme Performance summer tires will work great with these fitments, depending on your personal ratio of street to track driving.

Nitto NT01 (100TW) - The NT01 is one of the highest performing track day tires on the market and is available in all of the most popular sizes. This tire is not recommended for a daily driven car, or even for a car that is driven to and from the track. These tires will wear extremely quickly and are best used for cars that are trailered to and from events.

Hankook Ventus R-S4 (200TW) - For drivers who are looking for a dual duty tire that can hold its own on the street and on track. While this is not the fastest track day tire available, it is long lasting, and tire noise is kept to a minimum for those long drives to and from the track. These tires are more than capable of setting impressive times on track, despite their great manners on the street.

Bridgestone Potenza RE-71R (200TW) - For drivers who are looking for a tire that can be used sparingly on the street, while still being capable of keeping pace with all other R compound tires on the track. The RE71R is one of the fastest tires available for track use, with the main downside being that these tires are made of a very soft compound that can wear quite quickly. This is an excellent tire for a track focused street car, that spends a majority of the time on track.

Nitto NT05 (200TW) - For drivers who are willing to sacrifice wet weather performance for a high level of dry weather traction. Can be daily driven but really only recommended for occasional drives on the street, and for track days where the driver can take advantage of all grip available.

Michelin Pilot Sport 4S (300TW) - For drivers who are looking for class leading performance on the street while still maintaining grip and longevity for occasional track days. This is the perfect tire choice for the enthusiast who does a majority of their driving on the road, while attending 2-3 driving events per year.

 

Our Recommendations

The Light & Wide Square Wheel Package
Light. Wide. Rotatable. The lightest 17" square setup available to properly support 255 tires. Best if you plan to keep stock brakes or one of the smaller aftermarket brake setups with rotor diameters of 355mm or less. While negative camber may not be required, it is strongly recommended for track use. Tires are less expensive to replace when needed, which keeps running costs down.

• Front & Rear: 17x9.5” ET35 with 255/40-17 tires
  
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
  • Rear 12mm spacers recommended for aesthetics. The effective rear offset of ET23 gives you the look of a more flush staggered fitment while retaining the ability to rotate tires front-to-rear.
  • 275/40-17 tires can also be used, but will require 2.5 degrees of front negative camber or more.

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Square 18" Street-Friendly Wheel Package
Our best-selling setup. It's no coincidence that you'll see this fitment on most E46 M3s at the track. It's a rotatable square fitment that supports 265 or 275 tires with zero or minimal modifications. May require spacers, but has a very street-friendly front camber requirement. Huge variety of tire brands and compounds available.

• Front & Rear: 18x9.5” ET35 with 265/35-18 or 275/35-18 tires
  
  • 265/35-18 requires at least -1.5 degrees of front negative camber.
  • 275/35-18 requires at least -2.0 degrees of front negative camber.
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
  • Rear 12mm spacers recommended for aesthetics. The effective rear offset of ET23 gives you the look of a more flush staggered fitment while retaining the ability to rotate tires front-to-rear.
  • With certain tire brands and low ride heights, front fender liner rubbing may occur.

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Square 18" Street/Track Wheel Package
Coilover-friendly with minimal camber requirements. This fitment serves as a middle-ground between the ET22 and ET35 setups. It simulates running 7mm spacers on the ET35 setup, which makes it perfect for clearing nearly all aftermarket suspension setups without adding spacers.

• Front & Rear: 18x9.5” ET28 with 265/35-18 or 275/35-18 tires
  
  • 265/35-18 requires at least -2.0 degrees of front negative camber.
  • 275/35-18 requires at least -2.5 degrees of front negative camber.
  • Rear 12mm spacers recommended for aesthetics. The effective rear offset of ET16 gives you the look of a more flush staggered fitment while retaining the ability to rotate tires front-to-rear.
  • With certain tire brands and low ride heights, front fender liner rubbing may occur.

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Square 18" Track Wheel Package
When track days are more than just a hobby. Similar to the above, but this setup's lower ET22 offset means no spacers are required. The trade-off is a more aggressive front camber requirement. The camber required for this setup makes it very aggressive for street use. Tramlining may occur on grooved streets as a result.

• Front & Rear: 18x9.5” ET22 with 265/35-18 tires or 275/35-18
  • 265/35-18 requires at least 3 degrees of front negative camber.
  • 275/35-18 requires at least 3.5 degrees of front negative camber.
  • With certain tire brands and low ride heights, front fender liner rubbing may occur. 

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The Light & Wide Staggered Wheel Package
Low-cost, high grip. The lightest possible staggered setup to properly support 275 rear tires. Ideal if you plan to use stock brakes or one of the smaller aftermarket brake setups with rotor diameters of 355mm or less.

• Front: 17x9” ET30 with 245/40-17 tires
  Rear: 17x10” ET25 with 275/40-17 tires
  • Direct fit.
  • 255/40-17 front tires can also be used as a direct fit.
  • With certain tire brands and low ride heights, fender liner rubbing may occur.

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The Bolt-On Staggered Wheel Package
Rear grip for the street or strip. Fill out the wheel wells while running wide rear tires. Accommodates many brake setups with rotors up to 380mm in diameter.

• Front: 18x9" ET30 with 245/40-18 tires
  Rear: 18x10" ET25 with 275/35-18 tires
  
  • Direct fit.
  • 255/35-18 front tires can also be used as a direct fit.
  • With certain tire brands and low ride heights, fender liner rubbing may occur.

VS-5RS // Front & Rear: 18x11 ET25 with 30/65-18 (other mods shown)

Recommended for: All hardcore track enthusiasts, time trailers and W2W Club Racers. This category prioritizes performance above all-else, and includes both staggered and square configurations to best suit each individual drivers priorities, goals and preferences for their vehicle. Motorsport oriented suspension setups with aggressive negative camber specifications are par for the course here, unless class rules prevent such modifications.

We are passionate about motorsports, and we’ve done our homework. Before developing wheels for a particular chassis we review class rules from popular racing organizations like SCCA, NASA, PCA, POC and more. To keep you competitive, we’ve included our recommended wheel fitments, and to keep you compliant, we’ve conveniently added class rules and regulations as they relate to wheels and tires.

Additional Factors: The following items should be considered when choosing a fitment from this category.

• Square vs. Staggered
• How to Prevent Rubbing
• Will Your Suspension Clear?
• Will You Need Negative Camber?
• Wheel Diameter
• Brake Clearance (if using aftermarket big brake kit)
• Do you Plan To Compete in Classed Events?

Recommended Tires: In order to get the most performance out of the other modifications you've done that are required to use these fitments, these setups should only be used with aggressive tire compounds such as the Nitto NT01 or Hoosier R7.

Nitto NT01 (100TW) - The NT01 is one of the highest performing track day tires on the market and is available in all of the most popular sizes. This tire is not recommended for a daily driven car, or even for a car that is driven to and from the track. These tires will wear extremely quickly and are best used for cars that are trailered to and from events.

Hoosier R7 (40TW) - The Hoosier R7 tires are as close as you can legally get to a full-on racing slick. These tires are recommended for race and autocross ONLY. Due to the tread pattern, these tires are not recommended for any street use, even when driving to and from an event. The Hoosier R7 is developed for drivers who compete in road racing or time trials, where responsiveness and high levels of grip in hot & dry conditions are desirable. The R7 is not designed for damp or wet conditions. The R7 is a rewarding tire for the enthusiast looking for the fastest and most consistent lap times. The R7 provides extended wear for this treadwear rating due to the tire compound being a bit harder than the Autocross-only “A7” variant.

If you are a racer and would like to see a new APEX wheel fitment, email us at expert@apexraceparts.com.

 

Our Recommendations

The 17" Square Race Wheel Package

Break records, not the bank. The lightest 17" square setup available to properly support 275 tires. This setup is for cars with track-focused high-clearance suspensions, other suspension setups will require spacers. Cars at this level should already be running the aggressive negative camber required to fit these wheels. Recommended only if you plan to use stock-sized brakes or one of the smaller aftermarket brake setups with rotor diameters of 355mm or less.

• Front & Rear: 17x10” ET25 with 275/40-17 tires
  
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
  • Requires at least 3.2 degrees of front negative camber.

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The 18" Square Race  Wheel Package
Look your personal best. The fitment you'll see on dedicated track cars everywhere. It's made to work with the mods you'll already have such as a high-clearance race suspension, aggressive negative camber, and upgraded brakes with rotors up to 380mm.

• Front & Rear: 18x10” ET25 with 275/35-18 or 285/30-18
  
  • 275 tires will require at least 3.2 degrees of front negative camber.
  • 285 tires will require at least 3.6 degrees of front negative camber.

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The Go-To Staggered Race Wheel Package
Put down the power. The fitment you'll see on dedicated track cars everywhere. It's made to work with the mods you'll already have such as a high-clearance race suspension, aggressive negative camber, and upgraded brakes with rotors up to 380mm.

• Front: 18x9.5" ET35 with 275/35-18 tires
  Rear: 18x10.5" ET22 with 295/30-18 tires
  • Available in all APEX designs.  
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
  • At least 3.2 degrees of front negative camber required.

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The Most Aggressive Race Wheel Package
Really put down the power. The most aggressive fitment we have available. Designed to fit cars with widebody kits or fender flares. Camber and spacer requirements vary depending on suspension type. Some level of trial-and-error is to be expected when mounting these wheels.

• Front: 18x10" ET25 with 275/35-18 tires
  Rear: 18x11" ET44 with 295/30-18 tires
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
  • At least 3.2 degrees of front negative camber required.

 

Race Class Rules

NASA German Touring Series (GTS)
The NASA German Touring Series is comprised of six classes of German cars organized strictly based on power-to-weight ratios. This simple formula provides broad flexibility in both vehicle choice and in the modifications allowed (which include just about anything). The result is a broad range of modifications and extraordinarily close racing. There are no specific rules dictating wheel and tire sizes, but we've listed our recommendations below:

Staggered Setups

• Front: 18x9.5" ET22
  Rear: 18x10" ET25
  • Front negative camber required.
  • No spacers required.
• Front: 18x10" ET25
  Rear: 18x11" ET44
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
  • Rear 20mm or larger spacers and rolled/pulled fenders required to prevent fender arch rubbing.

Square Setups

• Front & Rear: 18x10" ET25
  • Front 5mm or larger spacers required with certain aftermarket suspensions.
• Front & Rear: 18x11" ET44 with spacers
  • Front and rear 20mm or larger spacers required.
  • Front and rear negative camber required.
  • Front and rear rolled and/or pulled fenders or flares required to prevent fender arch rubbing.

Tire Options
All tires, whether DOT-approved or not, must be commonly available to all competitors from typical national retailers or directly from their respective manufacture. Special compounds not available to the public are not permitted.

• Dry Staggered Hoosier R7 - Front: 275/30-18 // Rear: 305/30-18
  
• Dry Square Hoosier R7 - Front & Rear: 285/30-18 or 305/30-18
  
• Wet Staggered Hoosier DOT - Front: 275/30-18 // Rear: 305/30-18
• Wet Square Hoosier DOT (Wet) - Front & Rear: 275/30-18 or 295/30-18

 

SCCA Autocross Stock Class (SS) Rules
Any type of wheel may be used provided it complies with the following:

1. Wheels must be the same width as stock.
2. Wheel offset must be +/- 7mm from stock.
3. Wheel diameter can be +/- 1" from stock.
4. Spacers are allowed as long as the final setup complies with the offset rule above.

Recommended for: Drivers who want a narrow, low-cost winter wheel & tire setup that will bolt-on without any additional modifications required. Whether you have an expensive set of street wheels to protect, or don't want to deal with visiting a shop for a changeover, having a second set of wheels with winter tires already mounted makes the process so much easier.

Additional Factors: The following items should be considered when choosing a fitment from this category.

• Brake Clearance (if using aftermarket big brake kit)

Recommended Tires: This depends on the conditions in which you plan to drive the car.

Deep snow & near/below freezing temperatures:
General Altimax Arctic 12 (studdable)

Some snow & near/below freezing temperatures:
Michelin X-Ice Xi3 (if snow will often be encountered)
Michelin Pilot Alpin PA4 (If snow will rarely be encountered)

 

Our Recommendation

Bolt-on Winter Setup
This winter setup can be used either with ice & snow tires or performance winter tires

• Front & Rear: 18x8.5" ET35 with 245/40-18 winter tires
  • Direct fit.

 

 Should I use a square or staggered setup? Which one will give me more performance? How wide should I go?

While there is no definitive right or wrong answer to these questions, there are some key variables that will help you answer these questions for yourself. Drivetrain layout, power output, suspension setup, and alignment settings can all contribute to how your particular vehicle can take advantage of the distinct characteristics that each type of setup offers.

 

First of all, what's the difference?

 

Square Fitment: All four wheels are the same diameter, width, and offset. All four tires are the same size.

Staggered Fitment: All four wheels are the same diameter. Two wheels (typically the drive wheels) are wider.

 

It is possible to run a double-staggered (two wheels have a larger width and diameter) or a reverse-staggered fitment (front wheels have a larger width and/or diameter for brake clearance), and these setups only make sense in very specialized use cases.

 

Square Fitment Pros & Cons:

+ Tire Life & Running Costs: By allowing front-to-rear and left-to-right tire rotation, a square fitment will help you get the most miles out of your tires. By rotating your tires regularly, they'll last far longer and reduce operating costs. Track use and spirited driving will amplify these cost savings.

+ Handling: Equal tread width front and rear means the car will exhibit more neutral and balanced handling characteristics. This reduces or eliminates the tendency to understeer on a typical front-engined, rear-wheel-drive (FR) layout with a staggered fitment.

+ Simplicity:  Buying wheels and tires is just easier when they are all the same size. Keeping a spare is easier since you know it will fit the front or the rear if needed.

- Rear Traction: Rear grip is not optimized since the rear tire size is limited to the widest size that fits on the front.

- Aesthetics: Only some may consider this a con. Rear fitment may not be as flush as the front. However, spacers can be used to push the rear wheels out for a more aggressive look.

 

Staggered Fitment Pros & Cons:

+ Rear Traction: By fitting a wider tire on the drive axle, you'll have more available traction in higher-horsepower vehicles. This is most useful in straight-line acceleration from a stop and when exiting a corner.

+ Aesthetics: Both the front and rear wheels can sit flush with the fenders without requiring the use of spacers.

+ Retain Factory Handling - Most RWD vehicles come with staggered fitments from the factory. By sticking with this layout you can retain the handling characteristics of the car that you're already familiar with.

- Tire Life & Running Costs: Tires cannot be rotated front-to-rear, so tire life will be reduced. This is more apparent during track/spirited driving.

 

How bad is rubbing, really?
It depends on the severity. Minor rubbing is sometimes considered par for the course with the tradeoff being substantially increased performance as a result of a much wider wheel and tire setup. Major rubbing can be a big annoyance, and should definitely be dealt with.

Our goal is to provide fitments that allow for wide, aggressive tires that will not rub under any driving conditions. Most tire rubbing occurs during suspension compression such as hard cornering or driving over large bumps.

Every chassis has some room to go wider than the factory setup without additional modifications. However, when it comes to maximizing the potential of your chassis, you gotta pay to play. This means that in order to run those 18x10" ET25s up front with 275s, you're going to need to do some work. There are three main types of rubbing that can happen when pushing the limits of tire width.

Type of Rubbing	Recommended Solutions (In Order of Preference)
Fender arch rubbing - The outer shoulder of the tire rubs the inside of the fender arch sheet metal.	Roll or pull the effected fenders Add negative camber Reduce tire size or add fender flares
Fender liner rubbing - The outer shoulder of the front tires rub the front plastic fender liners while making full-lock turns.	Add front negative camber Reduce tire size Remove fender liners
Suspension rubbing - The inside shoulder of the front tires (or the lip of the wheel itself) rubs the front suspension components, which can prevent mounting the wheel at all.	Add spacers Change spring configuration by either removing helper springs, or by using a shorter main spring Adjust ride height Reduce tire size

 
Reasons For Using Spacers

1. To clear certain aftermarket suspension setups
2. To clear certain aftermarket big brake kits
3. To achieve a perfectly flush fitment with the fender arches
4. To make a rotatable square setup fit like a staggered setup

When installed properly with the correct extended hardware, spacers are often the most cost-effective way to achieve a perfectly-dialed-in fitment; the alternative being expensive custom-offset wheels.

What You Need To Know
There are countless horror stories floating around about spacers, and we want to clear up the misconceptions. Always take the following things into consideration when installing spacers:

Spacer Quality - Do not buy the cheapest ones you can find. A spacer is the only piece of hardware between your wheel and the vehicle's hub. Machining errors are quite common with bargain-priced spacers. This can lead to an improper seat and ultimately spacer or hardware failure resulting in vehicle damage and injury.

Always Use Extended Hardware - We know it can be tempting to re-use your stock lug bolts with spacers. However, even a 3mm spacer will reduce the stock lug bolt thread engagement by 19%. 5mm spacers reduce it by 30%. This is a significant reduction in strength in one of the most-stressed components of your vehicle. Using the correct extended hardware ensures proper thread engagement and should be considered a requirement when installing spacers.

Ensure Proper Installation - Spacers can only be installed one way. This should be obvious, but first-time installers (both shops and owners) have been known to install 3mm or 5mm spacers backwards.

Ensure all wheel bolts or lug nuts are torqued to the manufacturer's recommended torque specification.

Before lowering the car on the ground, spin each wheel slowly by hand. This ensures that you're using the correct-length hardware which, if too long, can damage braking components located behind the hub. Check the inner clearance of the wheel and tire to the nearest suspension components and ensure at least 3mm of clearance. For the front wheels, turn the steering wheel lock-to-lock and check the clearances of the tire to the fender liners. Do this again once the car is on the ground with the suspension settled.

Click to enlarge

High-Clearance
Adjustable coilovers like JRZ, MCS, Öhlins TTX, TC Kline, Ground Control, and more.

Medium Clearance
OEM Suspension (including M-Sport), OEM shocks with aftermarket lowering springs, aftermarket sport shock & spring kits, some aftermarket coilovers like BC Racing, and more.

Limited-Clearance
Adjustable coilovers like KW (V1, V2, V3, Clubsport), ST (X & XTA), Öhlins R&T, height-adjustable sleeve kits from KW, and more

 

 

Why Is This Important?

Our goal is for the wheels, tires, and suspension to work harmoniously together to extract the best possible performance from the car without rubbing. If maximizing wheel and tire width is important to you, it is imperative to consider the form factor of your current suspension setup prior to purchasing a new set of wheels and tires. This is also an important factor to consider upon upgrading your suspension. While you may not have immediate plans to push the limits of wheel and tire width, we encourage you to plan for the future by choosing a setup that aligns with your future plans and goals for the car.

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Taking a closer look at the E46 M3 shown in the photo above, we can clearly see how the overall suspension layout varies between the front and rear of the car. When comparing the differences in these two suspension configurations, it becomes clear as to why so much more emphasis is placed on front clearance as opposed to the rear. The factory BMW suspension consists of a coilover (coil spring over shock) design in the front, and a “divorced” spring and shock configuration in the rear. This “divorced” configuration places the springs inboard on the rear control arms, leaving ample clearance for a wider rear wheel and tire setup. A vast majority of enthusiasts choose to keep a divorced rear suspension configuration, even in cases where the car is being heavily modified for track work.

Many enthusiasts are under the impression that negative camber is just a way to install ridiculously wide wheel and stretched tire fitments under their fenders – a way to get hellaflush status and Instagram fame. We, on the other hand, have lengthy camber discussions with our clients in regards to wheel and tire fitment, track preparation and all things related to squeezing the most out of their machine. During these conversations, we often discover that enthusiasts who are new to the sport carry a sour connotation with negative camber, and a general misunderstanding of the role it plays in the world of performance driving. It is true that aggressive amounts of negative camber can help you stuff those new, wider rollers under your car, but it happens to serve a greater purpose, one that is foundational in the world of Motorsports; tire bite.
  
How much negative camber is enough?
Too much negative camber will result in unpredictable handling and premature inner tire wear. Not enough negative camber will cause understeer and premature outer tire wear.

IN GENERAL, you can use the specs below to get yourself in the ballpark of what will work best for your car and driving style. There are other important variables such as spring rate, tire compound, aerodynamics, etc that will come into play, but these recommendations can serve as a starting point.

 

Typical Camber Recommendations
Stock alignment:	Front: -0.5º to -1.0º Rear: -1.0º to -1.5º
Daily spirited driver / occasional track day:	Front: -1.5º to -2.0º Rear: -1.8º
Frequent track day warrior:	Front: -2.5º to -3.0º Rear: -1.8º
Dedicated track car:	Front: -3.2º to -3.8º Rear: -2.2º

 

All of our wheels clear the OEM brakes of the vehicles they were intended for, usually with room to spare. We spend lots of time designing our barrels and spokes to clear as many aftermarket big brake kits as possible.

OEM Brakes
These are typically the most generous in terms of wheel clearance. On the E46 there are no clearance issues with stock brakes (including Competition/CSL setups) on any of our recommended fitments.

Aftermarket Big Brake Kit
There are many different types and sizes of aftermarket brakes available. We've tested many popular configurations and have listed them in the brake fitment table below.

Generally speaking, we recommend the smallest possible diameter that clears the brakes. This minimizes weight, reduces wheel and tire costs, and has a very functional and performance-oriented look.

17"
The lightest wheels we make. Clears all stock brake setups, but may limit upgrade options. Taller tire sidewalls can be used, which will improve ride quality and offer additional protection for the wheels against road hazards. Tire brands and sizes can often be limited, so check to ensure the sizes and compound you'll need are available.

18"
Right in the middle. 18" APEX wheels clear nearly every brake upgrade option available for the E46 M3, and give you the best selection of tire brands, sizes, and compounds. Wheel & tire prices are slightly higher than 17" wheels, but typically far less than 19" wheels. Tire sidewall height is slightly smaller than 17" wheels and therefore ride quality and wheel protection are marginally reduced.

19"
We get it. Sometimes larger wheels just look better. Brake clearance won't likely ever be an issue, and the 19" tire availability and selection grows more each day. A 19" wheel+tire weighs about the same as an 18" wheel+tire with the same overall rolling diameter, so weight is considered negligible between 18" and 19" setups. Wheels and tires are more expensive, and shorter tire sidewalls mean a more communicative ride (you'll feel the bumps) and less protection for the wheels.

Certain race classes such as NASA GTS3 and BMW CCA Stock Autocross require that specific wheel and tire sizes be used. Some classes have a range of specifications that work, while others require an exact size. Be sure to check with the appropriate organization to ensure your setup will comply with these rules. View our recommendations in the Race Fitments section below.