Quick Answer

For most Subaru WRX models, a 15mm to 20mm wheel spacer is the sweet spot for a flush fitment without rubbing. If you're running stock wheels, 15mm front and 20mm rear is a common setup. Always prioritize hub-centric spacers and proper installation for safety.

The Subaru WRX is a driver's car, and nothing transforms its stance like a set of wheel spacers. Whether you're aiming for a track-ready look or just want the wheels to sit flush with the fenders, choosing the right thickness is crucial. Too thin and you won't see a difference; too thick and you'll risk rubbing and premature bearing wear.

This guide breaks down the factors that determine the ideal wheel spacer thickness for your WRX, from wheel width and offset to suspension setup. We'll also highlight some compatible products from AFD to help you complete your build.

Why Wheel Spacer Thickness Matters

Wheel spacers push your wheels outward, effectively reducing the offset. This can improve handling by widening the track, but it also changes the load on your wheel bearings and suspension components. The key is to choose a thickness that achieves your desired look without compromising safety or performance.

The stock WRX wheels typically have a +55mm offset. Adding a 15mm spacer effectively brings that to +40mm, which is a popular choice for a flush fit. A 20mm spacer gives a more aggressive stance but may require fender rolling on lowered cars.

  • Start with a moderate thickness like 15mm to assess fitment.
  • Check for clearance between the tire and suspension components after installation.
  • Always use hub-centric spacers to reduce vibrations.

Choosing the Right Thickness for Your Setup

Your ideal spacer thickness depends on your wheel width, offset, and tire size. For stock wheels (18x8.5 +55), a 15-20mm spacer is typical. If you have aftermarket wheels with a lower offset, you may need thinner spacers or none at all.

If your WRX is lowered, you'll need to be more cautious. Lowering reduces suspension travel and can cause rubbing on bumps. In that case, 15mm is often the safest maximum. For a stock-height WRX, 20mm is usually fine.

Consider the type of driving you do. For daily driving and occasional spirited runs, a conservative 15mm is a safe bet. For track use, you might want to fine-tune with smaller increments, but always prioritize clearance and safety.

  • Measure your current wheel gap and fender clearance before purchasing.
  • Consult with a professional if you're unsure about fitment.
  • Re-torque your lug nuts after 50-100 miles of driving.

Installation Tips for Wheel Spacers

Proper installation is critical for safety. Always clean the hub surface and the spacer before mounting. Apply a thin coat of anti-seize to prevent corrosion, but avoid getting it on the lug studs or bolts.

Torque the lug nuts to the manufacturer's specification in a star pattern. After driving for a short distance, re-check the torque to ensure everything is secure. If you experience vibrations, the spacers may not be hub-centric, or they may be improperly seated.

Consider upgrading to extended studs if you're using spacers thicker than 15mm. This ensures adequate thread engagement and prevents wheel loss.

  • Use a torque wrench for precise tightening.
  • Inspect spacers for any signs of damage before installation.
  • If you're unsure, have a professional install them.

Decision Rules for Choosing Spacer Thickness

  • Stock wheels, stock suspension: A 15mm to 20mm spacer is ideal for a flush look without rubbing. Start with 15mm for a safe, conservative stance. 15mm is the safest starting point.
  • Lowered suspension: With a drop, reduce spacer thickness to avoid rubbing. 10-15mm is often the maximum, depending on the drop and fender clearance. Stick to 10-15mm and test fitment carefully.
  • Aftermarket wheels: Check the offset of your new wheels. If they already have a lower offset (e.g., +35 to +45), you may not need spacers at all, or only thin ones like 5-10mm. Measure your existing clearance before adding spacers.

AFD Products for Your WRX Build

  • AFD GT3 Forged Wheels: Crafted from elite 6061-T6 forged aluminum for maximum strength at minimal weight, with a center-lock aesthetic inspired by GT3 racing. Pairing lightweight forged wheels with the right spacers can dramatically improve handling and reduce unsprung weight, enhancing both performance and looks.
  • 2015-2021 Subaru WRX/STI AFD V1 Lip: Available in Gloss Black or Matte Black, this 3-piece front lip is built from Hybrid Poly material that flexes under pressure and resists cracking from daily road wear. A front lip not only enhances the aggressive look of your WRX but also complements a wider stance created by spacers, improving the overall aesthetic coherence.

Who Should Use Wheel Spacers

Best For

  • Enthusiasts seeking a more aggressive, flush stance without buying new wheels.
  • Drivers who want to improve cornering stability by widening the track.

Not For

  • Those who prioritize maximum performance and minimal unsprung weight; consider forged wheels like the AFD GT3 instead.
  • Drivers with heavily lowered cars who can't risk any rubbing; they may need fender work or a different approach.

Choosing the right wheel spacer thickness for your Subaru WRX is a balance of style, safety, and performance. Start with a moderate size, test fitment, and always prioritize quality hub-centric spacers. For a complete upgrade, consider pairing spacers with lightweight forged wheels like the AFD GT3 Forged Wheels to transform your WRX's stance and handling.