FITMENT LAB
FITMENT-VERIFIED

2023 PORSCHE 911 GT3 RS · 992 · KNOWLEDGE CARD · SPECS READ 2026-09-18 · CATALOG VERIFIED SEP 4, 2026

2023 Porsche 911 GT3 RS — wheels, tires, fitment and brakes

IN SHORT

13 facts with a source, 6 marked missing. centerlock, 20–21-inch, ET25 to ET55; 1 listed wheel models pass the fitment gate. Nothing on this page is inferred: a row without a source says missing.

01Wheels

FACTVALUESOURCE
OE wheel, front10J × 20 ET45, forged, center-lockPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section · Fitment fixture data/fitment-fixtures.json (992-GT3RS): APEX 992.1 GT3 RS fitment guide; retailer by-vehicle listing Sep 2 2026
“The new 911 GT3 RS comes standard with forged aluminum alloy center-lock wheels.”
forged aluminum center-lock per Porsche; width/offset from the fixture
OE wheel, rear13J × 21 ET31, forged, center-lockPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section · Fitment fixture data/fitment-fixtures.json (992-GT3RS): APEX 992.1 GT3 RS fitment guide; retailer by-vehicle listing Sep 2 2026
Bolt patterncenter-lock (no bolt-on pattern)Porsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section · Fitment fixture data/fitment-fixtures.json (992-GT3RS): APEX 992.1 GT3 RS fitment guide; retailer by-vehicle listing Sep 2 2026
Hub boremissingmissing · Not applicable to a center-lock hub in the bolt-on sense; no figure held.
Accepted offset rangeET25 to ET55Fitment fixture data/fitment-fixtures.json (992-GT3RS): APEX 992.1 GT3 RS fitment guide; retailer by-vehicle listing Sep 2 2026
Minimum wheel diameter (brake clearance)20 in front / 21 in rearFitment fixture data/fitment-fixtures.json (992-GT3RS): APEX 992.1 GT3 RS fitment guide; retailer by-vehicle listing Sep 2 2026
center-lock only; the retailer lists two center-lock models

02Tires

FACTVALUESOURCE
OE tire, front275/35 R20Porsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
“Road-legal sports tires measuring 275/35 R 20 at the front and 335/30 R 21 at the rear”
OE tire, rear335/30 R21Porsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
Load indexmissingmissing · Not stated in the press kit; the tire's own marking is the source.
Speed ratingmissingmissing · Not stated in the press kit.
Tire pressure placardmissingmissing · Not read from a manufacturer document yet.

03Brakes

FACTVALUESOURCE
Front rotor408 mm × 36 mm, ventilatedPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
“brake discs with a diameter of 408 millimeters are used on the front axle … the thickness of the discs has been increased from 34 to 36 millimeters”
Front rotor thickness36 mmPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
The fixture previously held 34 mm (the GT3 figure); corrected to Porsche's stated 36 mm on 2026-09-18.
Front caliper6-piston aluminum monobloc fixed, 32 mm pistonsPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
“Aluminum monobloc fixed-caliper brakes with six pistons each … piston diameters have been increased from 30 to 32 mm”
Rear rotor380 mm, ventilatedPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
“The rear axle continues to be fitted with 380-mm brake discs and four-piston fixed-caliper brakes.”
Rear caliper4-piston fixedPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
Optional brakePCCB: 410 mm front / 390 mm rearPorsche Newsroom — '992 911 GT3 RS Press Kit' (PDF), Chassis section
“The optionally available Porsche Ceramic Composite Brake (PCCB) has 410-mm discs on the front axle and 390-mm discs on the rear axle.”
Pad shape, front (FMSI)missingmissing · FMSI pad shape not read from a brake maker's own catalog yet.
Pad shape, rear (FMSI)missingmissing · FMSI pad shape not read from a brake maker's own catalog yet.

408mm front rotors and center-lock hubs: 20-inch front / 21-inch rear center-lock wheels only. Source: Porsche Newsroom 992 GT3 RS press kit (408 mm front discs, 36 mm thick, 6-piston monobloc; 380 mm rear; PCCB 410/390) — corrected from 408x34 on 2026-09-18; APEX 992.1 GT3 RS fitment guide brake clearance list; retailer by-vehicle results (2 center-lock models).

BRAKE CLEARANCE · ROTOR VS NOMINAL RIM DIAMETER rotor Ø 408 mm rim 20" = 508 mm 50 mm radial room at the rim lip Minimum wheel for this car: 20" Caliper profile and the wheel's spoke and barrel depth are not in our data: this is diameter only, not a caliper clearance measurement.

04What fits (from the fitment gate)

1 listed models pass for the 2023 Porsche 911 GT3 RS; 1 have a maker reference image. Every one below was checked for bolt pattern, diameter, width, offset and brake clearance against the rows above.

STANCE · SEEN FROM ABOVE · HUB FACE AT 0 · OUTBOARD → hub mounting face OE 20×10 ET45 · 275/35R20 NEW 20×10 ET45 · 275/35R20 0 mm outboard face vs OE (same) inboard face: 0 mm vs OE (negative = closer to the suspension). Dashed band = tire section width at nominal size. Fender and suspension clearance are not in our data: this is geometry relative to OE, not a rub verdict.

05What almost fits, and why

No listed wheel sits at the edge of the range for this car.

06Tire sizes

OE 275/35R20 front / 335/30R21 rear. Listed alternates: 275/35R20, 335/30R21.

TIRE SIZE · DRAWN TO SCALE · DASHED = RIM 275/35R20 335/30R21 Ø 701 mm · sidewall 96.3 mm Ø 734 mm · sidewall 100.5 mm +4.8 % rolling diameter — over 3 % Speedometer reading 60 → actual 62.9 (+4.8 %). Computed from nominal size; real tires vary by make.

07Pads — compounds by use, in the makers' own words

Street compounds bite from cold and dust less; track compounds need heat (Hawk's DTC ranges start at 400 °F) and are not listed for street. EBC says Yellowstuff is a street pad and that track use pushes past its 400 °C fade threshold. None of these makers publish a per-car pad recommendation here; per-car part numbers are missing until read from the maker's catalog.

COMPOUNDSTATED TEMPERATURESDUST / NOTESSOURCE
EBC Brakes Redstuff Ceramic
fast street; 'Race Use: No'
not stated'Dust Rating: Low' — 'reducing dust by 60–90%'
EBC: 'lowest dust fast street pad'; 'Nominal friction coefficient 0.5'; bed-in 'can be as long as 1000 miles'; ECE R90 approved (most part numbers).
EBC Brakes — Redstuff Ceramic Brake Pads
EBC Brakes Yellowstuff (4000 series)
fast street; not recommended by EBC for dedicated track use
fade threshold 400 °C (750 °F) — 'the maximum expected temperature in fast street driving'not stated as low dust
EBC: 'We no longer recommend Yellow for dedicated track use'; 'track conditions can push brake temperatures above 500–600 °C (1100 °F)'. R90 approved for street use in Europe.
EBC Brakes — EBC Yellowstuff Fast Street Brake Pads
Hawk Performance HPS 5.0
street ('High Performance Street')
100–750 °F operating; 100–550 °F optimalnot stated
Hawk: 'shorter stopping distances, improved performance under heavy braking conditions, and street car friendly characteristics'; not compatible with carbon-ceramic rotors.
Hawk Performance — HPS 5.0
Hawk Performance HP+
'Ideal for Autocross' — low to mid temperature range; street + occasional track use per Hawk's placement
100–800 °F operating; 300–600 °F optimalnot stated
Not compatible with carbon-ceramic rotors.
Hawk Performance — HP+
Hawk Performance DTC-60
motorsport — 'Sports Car/GT/GS, Open Wheel/Formula' among the listed series
400–1600 °F operating; 700–1100 °F optimalnot stated
Race compound; Hawk lists it for competition series, not street. Not compatible with carbon-ceramic rotors.
Hawk Performance — DTC-60
Hawk Performance DTC-70
motorsport — 'extremely high torque and highly aggressive initial bite for cars with high deceleration rates'
400–1600 °F operating; 800–1200 °F optimalnot stated
Race compound; Hawk lists it as a split-friction partner with DTC-60. Not compatible with carbon-ceramic rotors.
Hawk Performance — DTC-70

Per-car pad part numbers and FMSI shapes: missing — not yet read from a maker's catalog. Brake buy links: none shown; no verified retailer brake URL is held for this vehicle.

?Questions answered from this data

Open the app on this car → All answer pages →