Porsche 911 GT3 RS 992.1 (2023–2026) Wheel Fitment Guide
The 2023-2026 Porsche 911 GT3 RS sits in a completely separate fitment universe from the GT3, GT3 Touring, and S/T despite sharing the same badge family. Where those three models use the Carrera-family body, the GT3 RS uses the Turbo-wide body — 48mm wider at the rear. That wider body requires wider wheels at a different offset: the GT3 RS runs 10″ fronts and 13″ rears versus the GT3’s 9.5″ and 12″. The GT3 RS wheel dimensions are not interchangeable with any other 992.1 model.
The GT3 RS ships exclusively with Michelin Pilot Sport Cup 2 tires on forged aluminum centerlock wheels. The Weissach Package upgrades these to forged magnesium, which alone saves approximately 8.7 kg / 19.1 lbs of unsprung and rotating mass. The standard 408mm steel brakes and optional PCCB ceramics both require a minimum 20″ front wheel — the same brake floor as the GT3 family. All GT3 RS builds are rear-wheel drive with PDK (no manual option), and rear-axle steering is standard.
Platform hardware is consistent with all other 992.1 centerlock models: single centerlock nut torqued to 600 Nm / 444 lb-ft with a calibrated centerlock torque tool, no spacers compatible, and direct TPMS sensors must be transferred or replaced when fitting aftermarket wheels.
About this guide: The fitment data below is compiled from owner-submitted builds and enthusiast forum research across Rennlist's 992 GT3 / GT2 RS subforum and Planet-9. We summarize what 992.1 GT3 RS owners have reported running successfully so you have a researched starting point for your build.
Every FMB build goes through a sanity check and an engineering verification before forging. We cross-reference the configuration you're ordering against your trim and brake package and what's commonly documented on similar builds — and our manufacturing partner verifies the wheel itself (backspace, brake caliper clearance, structural spec) before production begins.
Fitment decisions involving ride height, tire choice, and suspension setup are yours and your installer's call. Use this guide as research, not as a substitute for a real fitment conversation.
Factory Wheel & Tire Configurations
The 992.1 GT3 RS has one standard wheel configuration and two optional upgrade packages — all sharing the same 10Jx20 / 13Jx21 dimensions. The difference between them is construction material and weight. The standard wheel and the lightweight aluminum are both forged aluminum; the Weissach magnesium is forged magnesium. None of these wheel packages cross-fit with the GT3 or GT3 Touring — they are GT3 RS-specific dimensions for the wider Turbo body.
Aftermarket Wheel & Tire Configurations
The 992.1 GT3 RS has the most extreme OEM offsets in the entire 992 lineup: ET45 front and ET31 rear with 10″ front and 13″ rear width. This is the platform’s practical maximum stance — the chassis was engineered around exactly these dimensions, and Porsche’s own GT department effectively did the aggressive offset work at the factory. As a result, the aftermarket reality on this platform is OEM-spec replacement in different constructions, not aggressive offset configurations. Owners pursue aftermarket wheels primarily for lighter alternatives to OEM aluminum at a more accessible price than OEM magnesium, or as track-day backup sets to protect the Weissach magnesium wheels from curb damage. Smaller front diameters (19″) are possible only with an aftermarket brake swap — neither the factory 408mm steel nor the 410mm PCCB ceramics clear a 19″ front. The setup below uses 20″ fronts and clears the factory brakes in both specifications.
The 992.1 GT3 RS is in a completely separate fitment universe from the GT3, GT3 Touring, and S/T. Despite sharing the same engine family and GT badge, the GT3 RS uses the wider Turbo body — 48mm wider than the GT3's Carrera-family body. The GT3 RS wheels (10Jx20 ET45 / 13Jx21 ET31) cannot be directly substituted with GT3 wheels (9.5Jx20 ET46 / 12Jx21 ET45), and vice versa. The rear ET31 offset on the GT3 RS is the lowest of any 992.1 wheel, required by the wider track width on the Turbo body. Both the standard 408mm steel brakes and optional PCCB ceramics require a minimum 20" front wheel. The centerlock nut must be torqued to 600 Nm with a calibrated centerlock torque tool — impact wrenches are never appropriate.
Flush Fitment
Staggered Setup
What Happens When You Build With FMB?
The configurations above are a starting point — not a final spec. When you start your build, here’s what actually happens before anything is forged:
- FMB sanity check. We cross-reference the configuration you’re ordering against your trim and brake package, and compare it to what’s commonly documented on similar builds. If the setup you want falls outside what we’ve seen work on this platform, we’ll flag it before you commit.
- Manufacturer engineering verification. Our manufacturing partner verifies the wheel itself — backspace, brake caliper clearance for your brake package, and structural spec — before production begins.
- Design render approval. You see the final design and confirmed specs before any aluminum is touched.
Ride height, tire choice, alignment, and suspension setup are variables your installer handles on the car — not things we verify from our end. That’s why we ask for the vehicle details we do on the build form: they’re the inputs we can actually check against.
FAQ - Frequently Asked Questions
No — the GT3 RS and GT3 use completely different wheels. The GT3 RS uses 10Jx20 ET45 front and 13Jx21 ET31 rear with 275/35ZR20 and 335/30ZR21 tires. The GT3 uses 9.5Jx20 ET46 front and 12Jx21 ET45 rear with 255/35ZR20 and 315/30ZR21 tires. The GT3 RS is 0.5″ wider at the front, 1″ wider at the rear, and runs a dramatically lower rear offset (ET31 vs ET45). These differences reflect the GT3 RS’s use of the wider Turbo body versus the GT3’s Carrera-family body. The wheels are not interchangeable.
The Turbo-wide body — 48mm wider at the rear than the Carrera-family body used by the GT3, GT3 Touring, and S/T. The GT3 RS shares its body width (1,900mm without mirrors) with the Turbo, Turbo S, and Sport Classic. The wider rear fenders accommodate the 13″ rear rim and 335mm-wide rear tire. This is why the GT3 RS is in a completely separate fitment universe from the GT3 family despite the shared badge and engine.
Standard delivery: forged aluminum centerlock, 10Jx20 ET45 front with 275/35ZR20 Michelin Pilot Sport Cup 2 tires, 13Jx21 ET31 rear with 335/30ZR21. Two optional upgrades share the same dimensions: the Lightweight Aluminum set (~1.3 kg / 2.9 lbs lighter per set, multiple finishes including Pyro Red, Neodyme, Indigo Blue, Satin Black) and the Weissach Magnesium set (~8.7 kg / 19.1 lbs lighter per set, comes with the Weissach Package). The standard, lightweight aluminum, and Weissach magnesium wheels are all identical in dimension — the differences are weight and construction material.
The Weissach Package bundles the forged magnesium wheels with additional CFRP (carbon-fiber reinforced plastic) components: front and rear anti-roll bars, rear coupling rods, and the rear axle shear panel. These replace equivalent components that would otherwise be made from steel or aluminum. The combination of magnesium wheels and CFRP chassis components reduces total vehicle weight meaningfully. The magnesium wheels alone account for approximately 8.7 kg / 19.1 lbs of the total weight reduction.
Standard: 6-piston 408mm front / 4-piston 380mm rear, cast iron, red calipers — same diameter as the standard GT3 / GT3 Touring brakes. Optional PCCB: 6-piston 410mm front / 4-piston 390mm rear, yellow calipers. Both configurations require a minimum 20″ front wheel. Aftermarket replacement rotors are available for both the steel and PCCB systems and remain compatible with OEM caliper hardware.
600 Nm / 444 lb-ft using a calibrated centerlock torque tool, per Porsche specification for all 992-generation centerlock wheels. Impact wrenches must never be used — they damage the anodized nut profile and prevent proper seating. Porsche specifies a programmed sequence: tighten to 600 Nm clockwise, reverse 60 degrees, then re-tighten to 600 Nm clockwise. For owners without the correct equipment, wheel changes should be done at a Porsche service center or a shop with the proper tool.
The primary aftermarket approach for the 992.1 GT3 RS is running OEM-spec replacement wheels (10Jx20 ET45 / 13Jx21 ET31) in aftermarket forged aluminum or magnesium construction — this preserves factory tire compatibility while potentially reducing weight versus OEM aluminum and cost versus OEM magnesium. Running 19″ front wheels requires replacing the factory front brakes — neither the standard 408mm steel calipers nor the 410mm PCCB ceramics will clear a 19″ front wheel. The market for validated GT3 RS-specific aftermarket fitments in non-OEM sizes is limited; OEM-size replacements in different constructions are the well-documented path on this platform.
pH-neutral cleaners only — this is non-negotiable for magnesium. Standard wheel cleaning products are typically alkaline or acidic and will corrode magnesium alloy over time, starting at seams and spoke edges. Use products specifically marked as safe for magnesium or explicitly pH-neutral. Regarding the Porsche Wheel Protection Plan: coverage terms vary. Some owners have reported successful claims on magnesium wheels; others find magnesium excluded in the written policy. Confirm coverage with your specific policy before incurring damage.
Both use the same Turbo-wide body and the same 5×130 / 71.6mm CB centerlock hub hardware, so the wheel will physically mount. However the dimensions are completely different — Turbo S ships with 9.5J×20 ET44 / 12J×21 ET70, while the GT3 RS uses 10J×20 ET45 / 13J×21 ET31. Mounting GT3 RS rear wheels on a Turbo S would result in approximately 52mm of additional protrusion at the rear (combining the 39mm offset difference with the wider 13″ rim adding 12.7mm more outboard at the face) — a magnitude that effectively prevents this swap without dramatic fender modification. Turbo S wheels on a GT3 RS would sit deeply tucked. These wheels are not interchangeable in practice.
2023-2026 USDM. The 992.1 GT3 RS was unveiled August 2022 and US deliveries began for MY2023. Porsche confirmed in October 2024 that the current 911 GT3 RS would continue for the 2025 model year unchanged, and the platform has continued through MY2026. The 992.2 GT3 RS has not yet been revealed. This guide covers the 992.1 generation only.
At stock ride height, the documented aftermarket setup on the 992.1 GT3 RS replicates OEM dimensions (10Jx20 ET45 / 13Jx21 ET31) in different construction materials. The platform’s OEM offsets are already at the practical maximum — ET31 rear is the lowest offset in the entire 992.1 lineup — so the aftermarket fitment universe on this platform is dominated by OEM-spec replacement rather than aggressive offset configurations. Owners typically pursue forged aluminum aftermarket wheels for lighter alternatives to OEM aluminum at a more accessible price than OEM magnesium, or forged magnesium aftermarket wheels for the lightest possible wheel set or a track-day backup for the OEM Weissach magnesium. Both constructions remount factory Cup 2 tires directly and clear both 408mm steel and 410mm PCCB front brakes at 20″ diameter. There is no spacer-based path on this platform — all wheel dimensional changes must be specified at the wheel itself. Going to 19″ front diameter requires replacing the factory front brake calipers with an aftermarket kit since neither the steel nor PCCB systems clear a 19″ wheel.
Every FMB order goes through a sanity check and an engineering verification before any aluminum is forged. First, our team cross-references the configuration you’re ordering against your brake package (408mm steel or 410mm PCCB ceramic) and Weissach Package status (standard aluminum vs magnesium wheels) and flags anything that falls outside what’s commonly documented on similar 992.1 GT3 RS builds. We confirm centerlock hub compatibility and rear-axle steering clearance on every build. Second, our manufacturing partner verifies the wheel itself — backspace, brake caliper clearance for your specific brake package, centerlock hub fitment, and structural spec — before production begins. You then approve the final design render and confirmed specs before any work starts. Ride height, tire choice, and alignment are things your installer handles on the car; the fitment guides on this site are researched starting points for making those decisions with your installer. The 600 Nm centerlock nut torque procedure is yours and your installer’s responsibility on every wheel install — the proper centerlock torque tool is a non-negotiable part of CL ownership.