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Big Brake Kit

XYZ Racing Hollow Rear Brake Kit — Audi S1 SPORTBACK (8X) (2015-2018)

SKU: XYZ-BRK-BKR-AU-12-REAR

  • IncludesRear axle pair (2 discs + 2 calipers)
  • PositionRear
  • Disc Ø380–421 mm
  • Caliper pots8-pot
  • Lead time10–15 working days

Fits Audi S1 SPORTBACK (8X) (2015-2018)

Brake pad compound

Street: quiet, low-dust, strong cold bite for road driving. Sport: higher temperature range and more bite for fast road and occasional track. Racing: maximum fade resistance for sustained track use (noisier and dustier cold). Match the pad to how hard you actually brake.

Disc size

Caliper grade

Hollow is the standard caliper: a lighter hollow-body forged caliper with a dust cover and a 5-year warranty. Hollow Racing drops the dust cover for sustained high-temperature use (rated to 1000°C, 2-year warranty) — the track-grade choice.

Caliper colour

Painted colours are included. Polished-forged finishes are mirror-polished forged calipers (Titanium, Gold, Silver); candy colours are a deep, mirror-reflection paint. Both are premium upgrades — fuller detail further down the page.

Painted — includedTell us the exact Pantone (PMS) code you want the calipers painted.Polished forgedCandy
Disc style

Drilled discs (cross-drilled holes) vent gas and water and look aggressive; slotted discs (surface grooves) wipe the pad face clean and resist fade under sustained hard use. Same price — choose on looks or how you drive.

Centre bell

The centre bell is the CNC-machined aluminium hat that joins the disc to the hub. Standard anodized is included; a two-tone bell adds an anodized accent ring in your choice of colour; titanium is the lightest, forged option.

Carbon-ceramic rotor

Carbon-ceramic rotors are a special-order track upgrade: far lighter than steel, fade-resistant at extreme temperatures and extremely long-lived. The price follows the disc size you choose above. The standard two-piece steel rotor is included.

Configured price£3,000.00Inc. VAT

Lead time: 10–15 working days from payment


£3,000.00

Made to order. Full payment is taken at checkout. Production begins once payment is confirmed.

Pay by card, Apple Pay, Google Pay — or Klarna on eligible orders.

Caliper render for this kit:

XYZ Racing Hollow Rear Brake Kit — Audi S1 SPORTBACK (8X) (2015-2018) — 380 mm
380 mm

The Audi S1 Sportback (8X) carries its quattro hardware over the shortest wheelbase in the A1 range, and the factory rear discs were specified for a warm hatch rather than the 231 PS turbo car this actually is. The XYZ Racing rear big brake kit replaces that undersized back-axle setup with a larger two-piece floating disc package that finally gives the rear of the car something to do under hard braking.

This is the rear-axle half of the story for a car that already loads plenty of weight onto its nose. On the S1, where the Haldex system can send drive rearward and the short body pivots quickly, stronger rear braking helps the car settle rather than skate when you stand on the pedal into a slow corner.

What this brake kit does for your 2015-2018 Audi S1 Sportback (8X)

Fitted to a 2015-2018 Audi S1 Sportback (8X), the first thing you feel is a firmer, more progressive pedal as the larger rear rotors add bite where the standard parts ran short. The bigger swept area sheds the heat that builds across back-to-back stops, so the pedal holds its travel after three or four hard applications instead of going long. A choice of Street, Sport and Racing pad compounds lets you set rear behaviour for daily driving, fast-road work or full track use without touching the hardware. The two-piece floating disc trims rotating mass at the back axle, which the short-wheelbase S1 reads as slightly crisper response over bumps. Braided lines keep the pedal firm as it heats. With included caliper colours of Red, Yellow, Gold, Black and Anodized Black at no extra cost, plus a custom Pantone option, the kit looks intentional behind the wheels.

About the rear big brake kit

XYZ Racing builds this as a rear-specific kit, bracketed for the S1’s back axle rather than adapted from a generic fitment. The headline feature is the two-piece floating disc, with hollow internal vanes for heat and a forged caliper that is hollow-bodied as standard. The calipers clamp larger discs than the factory items, and the assembly is offered with three pad compounds: a Street pad for quiet, low-dust road use, a Sport compound for harder fast-road driving and light track work, and a Racing pad for track sessions. Braided lines are included. Caliper colour is chosen when you order, from five included finishes or a custom Pantone shade, so the look is locked before the kit arrives. Discs come drilled or slotted at the same price, and the centre bell can be upgraded to two-tone anodized in five colours or titanium. The intent is balance: giving the rear enough braking authority to keep this AWD hatch composed under load, not overwhelming the front.

Fitment for the Audi S1 Sportback (8X) (2015-2018)

This kit is cut for the Audi S1 Sportback (8X) built between 2015 and 2018, the quattro-equipped hot version of the first A1, identified by its 8X chassis code. It is a rear-axle fitment, a pair of rear calipers and discs designed to bolt to the back of that specific car. Confirm your build year falls inside the 2015-2018 window before ordering.

What buyers also search for

  • Audi S1 Sportback rear brake upgrade for road and track use
  • Audi S1 8X big brake kit with Street, Sport or Racing pad options
  • Rear big brake kit for the 2015-2018 Audi S1 to improve braking balance
  • Audi S1 Sportback brake kit with Red, Yellow, Gold, Black, Anodized Black or custom Pantone calipers
  • Two-piece floating rear disc upgrade for the quattro Audi S1

Set your pad compound and caliper colour for your Audi S1 Sportback (8X) using the options above when you order.

What’s in the kit

Rear axle kit — supplied as a complete bolt-on assembly.

  • 2×Two-piece floating discs — 380–421 mm: you pick the exact diameter with the "Disc size" option
  • 2×Lightweight aluminium centre bells
  • 2×Forged aluminium calipers — 8-pot
  • 2×High-stiffness mounting brackets
  • 2×Braided stainless steel brake lines
  • 4×High-performance brake pads (1 set)
  • 1×Fitting hardware & tools pack

Parking brake: OE handbrake not retained — a hydraulic handbrake is required.

Choosing your spec

Every kit is built to order around the choices you make above. Here is what each option actually changes, so you can spec yours with confidence.

Brake pads — Street, Sport or Racing

Every kit ships with a full set of high-performance pads; the compound is your call.

Street is the right default for fast-road driving — a strong, progressive cold bite with low noise, low dust and long disc life. Sport raises the working temperature and adds bite and fade resistance for hard road use and the occasional track day, while still behaving on a cold morning. Racing is a track compound built for sustained abuse: huge fade resistance and bite once heat is in it, at the cost of more noise and dust when cold. Match the pad to how hard you actually use the brakes — there is no benefit to a race pad that never gets up to temperature.

Caliper grade — Hollow vs Hollow Racing

Hollow is the standard caliper on every kit: a hollow-body forged caliper, lighter than a solid one, fitted with a dust cover and backed by a 5-year oil-leak warranty. For most fast-road and spirited track use it is all the caliper you need.

Hollow Racing is the track-grade upgrade. It runs the same hollow body but without a dust cover (so there is nothing to melt at sustained high temperature), uses a twin-metal piston that isolates heat travelling from the disc to the oil seal, and is rated to 1000°C. Available 330–356mm (rear). Warranty is 2 years on oil leaks and 10 years on appearance. Built for professional racing and repeated track days.

Hollow Racing caliper

Caliper colour & finish

Painted colours (Red, Yellow, Gold, Black, Anodized Black) are included at no cost. Want an exact match to your car? Custom Color (+£150) paints the calipers to any Pantone code you supply (15–20 day lead time).

Polished Forged finishes are the flagship: a forged caliper given a mirror-polished surface treatment that shifts colour with the viewing angle. Beyond the looks, the polished surface dissipates heat better, resists rust and stands up to the weather. Choose Titanium (neochrome, +£350), Polished Gold (+£300) or Polished Silver (+£250). They look their best paired with a titanium centre bell. Care: clean only with a dilute neutral cleaner or water.

Candy colours (+£200) use a deep candy-paint and polishing process for a mirror-reflection, boutique finish — pick Teal, Blue, Red or Orange (shown below right).

Polished forged caliper finishes
Candy caliper colours

Centre bells

The centre bell is the CNC-machined aluminium hat that joins the disc to the hub. The standard anodized centre bell is included. The Two-tone bell (+£200) adds an anodized accent ring — choose Red, Yellow, Orange, Purple or Silver right here at checkout. The Titanium centre bell (+£500) is a forged titanium bell (bolts not included) that finishes off the polished-forged look.

Two-tone anodized centre bells
Same car

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