2018 Audi RS 7 Wheel Interchange

tl;dr

The 2018 Audi RS 7 uses 5x112, 66.5 mm center bore, and M14x1.5 lug bolts. The stock wheel is 20x9 ET35 with 275/35R20 tires. Use the on-page calculator to compare any donor wheel and tire to this baseline. Keep the setup hub-centric, clear the big brakes, and confirm load rating. When unsure, test fit before mounting tires.

Recommendation

As a technician, I treat the OEM set as the control. Build from there in small, measured steps.

Start with the baseline

Use the calculator methodically

• In Wheels from (donor), enter the wheel and tire you want to try.
• In Installed on (your vehicle), select 2018 Audi RS 7 and keep the OEM set.
• Adjust Custom wheel size: diameter, width, and offset.
• Adjust Custom tire size: section width and aspect ratio. Changing rim diameter updates tire diameter in the comparison.
• Watch inner clearance change, outer poke change, and overall tire diameter change.

Fitment guardrails I use

• Brake clearance first. The RS 7 has large front calipers. Ensure spoke-to-caliper and barrel clearance on a bare-wheel test fit.
• Hub-centric fit. The wheel center bore must be 66.5 mm. If larger, use quality 66.5 mm hub-centric rings.
• Load rating. Wheel and tire load index must meet or exceed OEM.
• Hardware. Match seat type to the wheel and keep proper thread engagement. Use M14x1.5 bolts of correct length for the wheel design.
• Diameter. Aim to keep overall tire diameter near stock unless you accept speedometer changes.

Impact

Here is how your inputs affect the car. Use these to interpret the calculator outputs.

• Offset change: More positive ET moves the wheel inward. Inner clearance decreases first. More negative ET moves outward, increasing poke and fender risk.
• Width change: Half the width increase goes inward, half outward. Combine width and offset to judge real clearance.
• Backspacing: Higher backspacing moves the barrel closer to suspension and brake lines.
• Overall tire diameter: Larger diameter raises the car, softens gearing, and reads slower on the speedometer. A 1% increase makes the speedo read about 1% low.
• Sidewall height: More sidewall rides softer, can feel less direct. Less sidewall sharpens response but reduces curb and pothole protection.
• Unsprung mass: Heavier wheels slow damping and can lengthen stopping distance.

Risks

• Caliper interference. The RS 7’s big brakes can hit spokes on some designs. Always test a bare wheel on the hub and spin it to check barrel contact.
• Fender contact. Outer poke increases with lower ET or wider wheels. Check at full lock and full bump with the calculator’s poke change as your guide.
• Hub vibration. Non-hub-centric fits can cause vibration. Use 66.5 mm rings when the wheel bore is larger.
• Lug seat mismatch. Audi OEM bolts often use a specific seat profile. If the wheel uses a different seat, change the bolts to match. Do not mix seat types.
• Hardware length. Too-short bolts reduce thread engagement. Too-long bolts can bottom out. Verify by hand before torqueing.
• TPMS and alignment. After any change, reset TPMS if needed and check alignment if the handling feels off.

Next actions

Checklist

• Confirm the OEM specs above against your door placard and manual.
• Open the calculator on wheelinterchange.com and set your baseline.
• Enter the donor wheel and tire. Tune width and ET until inner clearance and poke look safe.
• Keep overall diameter change small. Review speedometer impact in the results.
• Verify center bore is 66.5 mm or plan for hub-centric rings.
• Source bolts that match seat type and M14x1.5 thread. Hand test for engagement.
• Do a bare-wheel fit on the car. Spin for caliper and barrel clearance.
• Mount tires, torque to the factory spec from the owner’s manual, and re-torque after 50–100 miles.

Helpful tools

• 1/2 inch drive torque wrench
• M14x1.5 wheel hanger guide pin
• 66.5 mm hub-centric rings

If any spec varies by trim or package, verify with the calculator and your Audi documentation. When in doubt, test fit first. That saves tires and time.