Ultimate Guide to Track-Prepping Your Car RS5

For enthusiasts eager to push their Audi RS5 to the limit on a road course, this guide provides a stage-by-stage approach to optimize your car’s performance. Whether you’re a track day novice or a seasoned driver, understanding the necessary modifications will ensure a safer and more exhilarating experience with your Car Rs5. This guide focuses primarily on suspension and brakes, but also touches on engine and transmission enhancements to fully unleash your RS5’s track potential.

Stage 0: Baseline Car RS5 Prep – Ensuring Mechanical Readiness

Before hitting the track, a thorough mechanical inspection of your car RS5 is paramount. This Stage 0 checklist ensures your vehicle is in optimal condition to handle the stresses of track driving right from the showroom floor. The RS5 is inherently track-capable, but diligent preparation is key, regardless of your driving style. Smooth driving and car management will extend component life, but even then, aftermarket upgrades offer a performance and safety margin.

• Mechanical Overhaul: Ensure all fluids in your car RS5 are at Audi-specified levels. Scrutinize for leaks and address any mechanical issues or drivetrain error codes. Resolve any minor concerns before track day – track conditions will amplify existing problems.
• Fresh Brake Fluid: Brake fluid should be recent, ideally under two years old. A full brake bleed before each track event is highly recommended, but not the night before, as complete air removal may require a second attempt.
• Brake Pad and Disc Check: Verify brake pads and discs are well within factory wear specifications. Track driving is demanding on brakes, so starting with healthy components is crucial for your car RS5.
• Oil Change: Fresh engine oil is advisable, especially if nearing the end of your change interval. Consider a fresh oil change before track day to ensure optimal engine lubrication under high stress.
• Comprehensive Maintenance: Confirm all scheduled maintenance is up to date, including transmission and rear differential fluid services, to safeguard your car RS5’s drivetrain.
• Tire Inflation: Inflate tires to manufacturer-recommended pressures as a starting point. Experiment to find optimal pressures for your driving style and tire wear patterns on your car RS5.
• Tire Condition: Tires should have ample life remaining. Worn tires compromise safety and performance on the track.
• Spacer Legality: Be aware that most track event organizers prohibit wheel spacers. If your car RS5 uses spacers with OEM or aftermarket wheels, consider removing them for track events.
• Bodywork Security: Ensure all body panels, including undertrays, are securely fastened. High speeds can loosen unsecured components.
• Paint Protection: For paint chip prevention, painter’s tape is a traditional solution. Modern options include clear protection films, spray-on, or roll-on films that are peelable after the event, protecting your car RS5’s finish.

Stage 1: High-Performance Tires for Car RS5 – Grip is King

Once you’ve experienced the thrill of track driving in your car RS5, Stage 1 focuses on enhancing grip. Upgrading tires is the most impactful initial modification. Investing in the best track-oriented tires you can afford is paramount. Performance tires maximize the effectiveness of all other components and reveal any handling limitations in your car RS5. For many enthusiasts, sticky max-performance tires offer a significant upgrade while remaining streetable for the drive home after a track day.

Stage 2: Wheels, Tires, and Brakes for Car RS5 – Stepping Up Performance

Stage 2 involves a comprehensive upgrade to wheels, tires, and brakes, allowing your car RS5 to handle increased track demands. This stage addresses unsprung weight and braking efficiency.

• Aftermarket Wheels: Consider dedicated track wheels. Aim for lighter aftermarket wheels compared to OEM. Stock 20″ RS5 rotor wheels weigh around 35 pounds each (9″ wide). Forged aftermarket wheels can weigh 25 pounds or less in a wider 20″x10″ size. Lighter wheels improve handling and responsiveness. While forged wheels are stronger, remember that hitting rumble strips aggressively can still cause damage.
• Tire and Wheel Packages: Budget at least $2,000 for a quality tire/wheel package, with high-end forged wheel and tire combinations easily exceeding $5,500. Michelin Cup2 tires are a popular high-performance choice.
  • Tire Selection First: Decide on tires before wheels to ensure size compatibility and availability.
  • Wider Wheels: Consider 10″ or 10.5″ wide wheels for wider tire options, enhancing grip.
  • Width Considerations: Wider isn’t always better. “Over-tiring” your car RS5 without supporting modifications may not yield optimal results.
  • Tire Weight: Factor tire weight into your wheel choice. Wider tires (295mm, 305mm) can weigh significantly more than OEM 275mm tires, impacting overall rotational mass. Tire Rack provides tire weights on their website.
  • Tire Longevity: Balance outright performance with tire wear. Consider how frequently you are willing to replace track tires. Three-tenths of a second improvement might be less valuable than tire longevity for multiple track days per year. Track tires are consumables, factor replacement costs into your budget.

• Upgraded Brake Fluid: With stickier tires, upgrade brake fluid to one with a higher WET boiling point than OEM fluid. Wet boiling point is a more practical indicator of fluid performance life once opened. Castrol SRF is considered top-tier but expensive. Research and experiment with other brands that offer high wet boiling points for a balance of performance and cost.

• Track Brake Pads: Track-specific brake pads are essential for sustained high-temperature braking. They offer superior performance compared to street-biased pads and help keep your car RS5’s brakes running cooler. Pad choice is subjective, based on initial bite, modulation, and personal preference. Dedicated track pads will always outperform street pads in demanding conditions.

  • Bedding-In Pads: Bed-in new track pads to your rotors, and re-bed if swapping back to street pads. Some manufacturers, like Carbotech, offer pad compounds designed to be compatible for street and track without re-bedding. Carbotech provides helpful guides and support on their website.
  • Material Transfer: Understand that brake pad performance relies on material transfer to the rotors. Proper bedding ensures optimal performance and reduces wear.
  • RS5 Weight Consideration: The RS5 weighs over 4,000 lbs. Choose brake pads accordingly to handle the vehicle’s mass during track braking.

• RS5 Brake System Details:

  • Iron Brakes: The standard iron disc front brake system on the RS5 shares calipers and rotors with the Audi R8 equipped with iron brakes. Pads, rotors, and calipers are interchangeable.
  • Ceramic Brakes (CCB): RS5 carbon ceramic front brakes are exceptional and identical to the ceramic setup on the R8 V10 and Lamborghini Huracan (including Performance and Evo models), and even the Gallardo. The rotor size is 380 x 38mm, with Porsche 19Z calipers.
    • CCB Advantages: Reduced rotating and unsprung weight, superior fade resistance.
    • CCB Disadvantages: Extremely expensive to replace. Overheating CCBs causes resin outgassing and wear. Visual inspection may not reveal wear; weighing rotors or using a specialized Porsche laser tool is required for accurate wear assessment. Replacement ceramic rotors can cost $6,000 to $10,000+. Track use can significantly shorten their lifespan (potentially as little as four track sessions), while street use can extend life beyond 100,000 miles.
    • CCB to Iron Rotor Conversion: For track-focused RS5s with CCBs, consider replacing CCB rotors with iron rotors for cost-effectiveness. JHM and ECS Tuning offer 380x38mm iron rotors with correct offsets for CCB caliper compatibility. Racing Brake also offers CCB rotor replacements and iron rotor options.

• Brake Cooling: The RS5 lacks dedicated brake ducts for either iron or ceramic front brakes. Aftermarket brake duct kits are not readily available and would require custom solutions due to caliper and backing plate variations and suspension linkage constraints.

• Ceramic Brake Pad Options: Pagid offers RSC series brake pads (RSC1, RSC2, RSC3) for ceramic brakes, with increasing aggressiveness levels for track use.

• Rotor Upgrades:

  • Rear Rotor Upgrades (CCB and Iron): Rear rotor upgrades are possible for both CCB and iron brake equipped RS5s.
  • Front Rotor Upgrades (Iron): For iron brake cars, front and rear rotor upgrades are available. CCB cars are generally limited to rotor replacements unless converting to iron.
  • Two-Piece Rotors: Options include one-piece or two-piece rotors, and OEM size or larger diameter. Two-piece rotors can be semi or full-floating. Full-floating designs improve thermal expansion management and pad alignment under stress. Most two-piece rotors use aluminum hats and are often lighter and more cost-effective than OEM discs.
  • Larger Diameter Rotors: Upgrading to 380mm x 34mm front rotors (from 365mm x 34mm stock) with caliper spacers increases braking performance through added diameter and mass. Lightweight two-piece rear rotors are also available.
  • Two-Piece Rotor Manufacturers: Girodisc, JHM, Racing Brake, ECS, EBS, Brembo, and AP Racing are reputable manufacturers of two-piece rotors. Be aware of reported track durability issues with ECS two-piece rotors from RS5 and R8 owners.

Stage 3: Suspension Tuning for Car RS5 – Handling Precision

Stage 3 focuses on suspension upgrades to enhance handling and control for track driving in your car RS5.

• Sway Bars: Upgrading sway bars is a relatively easy and cost-effective first suspension modification. Replace front and rear bars as a set. While the RS5 exhibits balanced handling with slight oversteer when pushed, only upgrading the rear bar might induce excessive oversteer. Increased sway bar stiffness raises the effective spring rate, reducing body roll and improving control, but can negatively impact handling on rough surfaces.
  • Sway Bar Set Manufacturers: GMG (hollow), H&R, and Eurocode Tuning offer matched front and rear sway bar sets for the RS5.
• Springs: Lowering springs are a common upgrade, reducing ride height and lowering the center of gravity. However, they can place OEM dampers outside their optimal operating range, potentially causing premature damper wear. While many owners have had positive experiences with lowering springs, consider the long-term implications for damper longevity. Labor costs for spring replacement are significant, making coil-over upgrades a worthwhile consideration. Aftermarket shocks designed for lowering springs, like Bilstein offerings, are also an option.
• Coil-Over Dampers: Full coil-over kits offer matched springs and dampers, engineered for optimal performance. Damping characteristics are specifically tuned to the spring rate.
  • Linear vs. Progressive Springs: Linear springs provide consistent force throughout compression, offering predictable track handling and a “locked-in” feel. Progressive springs start softer and become stiffer with compression, providing better street comfort but potentially less predictable track behavior. High-quality dampers paired with linear springs can still offer good street ride quality.
  • Coil-Over Kit Manufacturers: Bilstein, KW, and Öhlins are leading manufacturers. KW offers a range from non-adjustable to two-way adjustable kits (note: rear compression adjustment on some KW kits requires damper removal). Öhlins offers a kit with linear springs. Bilstein provides kits with in-cockpit adjustable damping and manually adjustable options. All three brands offer height adjustability via spring perches. RS5 coil-over kits typically feature true coil-overs in the front and separate dampers and inboard springs in the rear.
  • Kit Application Considerations: Most full kits are designed to fit Audi A5, S5, and RS5 models. This raises the question of compromise, given the different weight distributions and overall weights of these models. Inquire if kits are specifically tuned for the RS5 or designed as a general fit.
  • Handling Benefits: Quality coil-over kits drastically improve handling, tire contact, and allow you to exploit the grip from upgraded tires and wheels. Some kits also offer weight savings over OEM components.

Stage 3.5: Bushings, Inserts, and Braces for Car RS5 – Stiffening the Chassis

Stage 3.5 includes bushings, inserts, and chassis braces to further refine handling and chassis rigidity in your car RS5. These are often relatively inexpensive and straightforward to install.

• Bushings and Inserts: These components limit movement in suspension and drivetrain mounts, leading to increased NVH (noise, vibration, harshness). Typically made from solid aluminum, they fill voids in factory rubber mounts in areas like transmission, differential, and rear subframe. Limiting movement improves responsiveness and control. 034 Motorsports and ECS Tuning are major suppliers.
• Chassis Braces:
  • Alu Kreuz (Underbody Brace): Replaces the OEM underbody brace below the oil pan. Billet aluminum construction in a boxed-X design, potentially lighter than the OEM stamped steel piece. Eurocode Tuning and 034 Motorsports offer versions.
  • Canyon Run CR-15 Bar (Strut Tower Brace): Fits behind the firewall, connecting strut towers to reduce chassis flex and improve steering feel and turn-in. Eurozone Tuning provides the CR-15 bar and installation videos.
  • Benefits: Chassis braces reduce flex, improve steering response and handling precision.
• Rear Differential Bushings/Inserts: The rear differential uses multiple bushings. A large bushing at the front of the differential and two bushings at the rear (sides) are common areas for inserts. Eurocode Tuning, 034 Motorsports, ECS Tuning, and Apikol offer inserts and bushings. Apikol’s polyurethane main rear differential bushing is customizable and allows some movement while improving control.
• Transmission Bushing/Insert: Transmission inserts and stiffer bushings reduce drivetrain slop for crisper shifts. 034 Motorsports offers transmission inserts and upgraded main bushings with higher durometer rubber.

Stage 4: Ultimate Track Car RS5 – Motorsports-Grade Upgrades

Stage 4 represents the pinnacle of track modifications for your car RS5, including big brake kits, roll bars, advanced chassis bracing, and motorsports-grade adjustable dampers.

• Motorsports Dampers: Double-adjustable motorsports-grade dampers, like the Öhlins kit available through PSI Shock, represent a significant upgrade over even high-end street/track coil-overs. Other manufacturers include JRZ, Moton (AST), Penske, but these are typically custom, very expensive ($5K+), one-off setups. AST offers a single-adjustable kit for the B8 platform, but Öhlins is generally preferred. Aragosta, a Japanese brand, offers excellent dampers but currently lacks RS5 applications.
• Avoid Entry-Level Brands: Steer clear of Korean/Taiwanese brands like Fortune, K-Sport, BC Racing, Megan Racing. While visually appealing, they generally lack the quality, tolerances, and engineering of Bilstein, KW, or Öhlins.

Engine and Transmission Tuning for Car RS5 – Power and Drivability

Engine and transmission tuning unlocks significant performance gains for your car RS5.

• JHM Motorsports Tuning: JH Motorsports (JHM) offers reputable and reliable engine (ECU) and transmission (TCU) tunes for the RS5.
  • Stage 1 (ECU Tune): Engine tune alone provides considerable horsepower gains (e.g., 25hp dyno-proven increase), enhancing overall driving enjoyment.
  • Stage 2 (ECU & TCU Tune): Stage 2 includes both ECU and TCU tunes. TCU tuning dramatically improves shift speeds, launch control aggressiveness, and driving characteristics in D and S modes. Stage 2 unlocks even more horsepower and transforms the driving experience for both street and track use. S mode becomes significantly more aggressive with enhanced throttle response. Stage 2 is highly recommended even for street-driven RS5s.
• Oil Coolers: Aftermarket engine oil coolers are currently unavailable for the RS5. However, the RS5 comes with a large factory Setrab oil cooler, exceeding the size of off-the-shelf Setrab units. The RS5 also features a main radiator and dual auxiliary radiators, generally sufficient for cooling. The ECU-controlled thermostat is a potential weak point, as it modulates coolant and oil temperatures.
• Transmission Cooler: The OEM transmission cooler is a liquid-to-liquid heat exchanger, using engine coolant to cool transmission fluid (ATF). This system is inadequate for track use. The gear side of the transmission lacks dedicated cooling.
• RMR Transmission Cooler: The RMR transmission cooler is an aftermarket solution that significantly improves transmission cooling. It’s a fully divorced system, independent of the engine radiator, reducing heat load on the engine cooling system and lowering overall transmission temperatures. The kit includes a new crossbar to enhance radiator airflow.

Plugs, Filters, and Oil for Car RS5 – Maintenance Essentials

• Spark Plugs: OEM spark plugs are sufficient for most RS5 applications. NGK 92400 Ruthenium HX plugs are a performance alternative with a different electrode design.
• Air Filters: K&N drop-in replacement air filters offer comparable performance to expensive carbon fiber intakes and are reusable after cleaning, suitable for track days.
• Engine Oil: High-quality engine oil is crucial, especially for track use. Group 4 full ester synthetic oils are preferred. Ensure oil meets Audi specification 502.00. Consider viscosity index and oil composition. True Group 4 oils are limited. 5,000-mile oil change intervals are recommended, especially with track use, instead of the 10,000-mile factory interval. Motul Sport 5w40 is a readily available ester-based full synthetic option. Consider oil analysis after track days to optimize oil selection.

This guide provides a comprehensive roadmap for track-prepping your car RS5. Remember to prioritize safety and gradual upgrades to fully appreciate the enhanced performance of your vehicle. Further stages and modifications may be explored as you gain more track experience.