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1. BMW M3 G80: A Braking Challenge

Stock Brake System Overview

The factory M3 G80 comes equipped with:

• Front brakes: 374mm ventilated discs with multi-piston compound calipers
• Rear brakes: 370mm ventilated discs with floating calipers
• Factory pads: Brembo performance compounds rated to approximately 400°C

For spirited road driving and occasional track sessions, these brakes perform adequately. However, the 374mm front rotor size represents a compromise between safety, everyday comfort, and cost—a reality across most production performance vehicles.

Optional M Carbon Ceramic Brake System

BMW offers an alternative factory option: the M Carbon Ceramic system, which upgrades to:

• Front: 400mm carbon ceramic rotors
• Rear: 380mm carbon ceramic rotors
• Advantage: Exceptional temperature management and reduced unsprung weight
• Limitation: Astronomical cost and poor cold-bite performance on daily drives

Why Stock Brakes Struggle on Track

The M3 G80's 1,730 kg curb weight combines with substantial power to generate serious thermal loads during sustained braking events. On the Nürburgring's demanding layout—particularly sections like the Bergwerk, Aremberg, and Eiskurve—or during multiple hot laps at Spa-Francorchamps, stock brakes experience:

• Brake fade: Progressive loss of stopping power as pad friction coefficient drops with temperature
• Rotor expansion: Larger rotors flex less under thermal stress
• Pad degradation: Factory pads reach optimal friction around 300-400°C; beyond this, performance deteriorates
• Heat transfer limitations: Smaller rotor surface area cannot dissipate energy quickly enough

Even a 20-minute track session can see temperatures exceed 600°C on the front rotors, well beyond the comfort zone of factory hardware.

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2. Why the M3 G80 Benefits from a Big Brake Kit

Performance Gains Beyond Numbers

A BBK isn't merely about installing larger rotors. A well-engineered system addresses multiple factors:

Increased Thermal Mass

Larger rotors (typically 380-390mm front) provide substantially more surface area for heat dissipation. The additional mass acts as a thermal buffer, keeping temperatures more stable during repeated braking events. This translates directly to consistent pedal feel and predictable deceleration throughout a track day.

Improved Cooling

Larger rotors paired with optimised caliper design (particularly 6-piston monoblock units) improve airflow dynamics. The additional exposed rotor surface and refined cooling fin geometry reduce lap times by maintaining consistent brake temperatures.

Caliper Stiffness and Response

Factory calipers use floating designs to reduce manufacturing complexity. Aftermarket monoblock calipers eliminate flex and provide more linear, responsive brake pedal feel. This precision matters enormously when trail-braking through technical corners.

Weight Considerations

While larger rotors add modest unsprung weight, most quality BBK systems use lightweight designs (forged calipers, 2-piece disc construction) that often weigh similarly to factory systems. The thermal advantages far outweigh any minor mass penalty.

Real-World Performance Example

Consider a typical European circuit track day at Brands Hatch:

• Stock brakes: Noticeable fade by lap 3-4; pedal travel increases progressively
• BBK system: Consistent braking performance across 15+ consecutive laps; pedal feel remains predicable throughout

The difference isn't subtle—it's transformative for drivers serious about maximizing their M3's potential.

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3. Big Brake Kit Options for the BMW M3 G80

AME Motorsport stocks several proven BBK solutions for the G80. Here's a detailed breakdown:

Brembo GT Series: Accessible Performance

Brembo GT Street Performance BBK

• Rotor size: 380mm front, 330mm rear
• Caliper type: 4-piston monoblock (front), floating (rear)
• Ideal for: Daily drivers who track occasionally
• Advantages:
• Proven Brembo engineering
• Excellent street manners
• Good thermal capability (600°C+)
• Moderately priced entry point
• Considerations: 4-piston front limits ultimate fade resistance during extended track use

Brembo GT-R Track-Focused BBK

• Rotor size: 380mm front, 330mm rear
• Caliper type: 6-piston monoblock (front), 4-piston monoblock (rear)
• Ideal for: Serious track enthusiasts
• Advantages:
• 6-piston front provides excellent stopping consistency
• Superior modulation compared to GT street version
• Better suited for multi-session track days
• Cross-drilled rotor design improves cooling

AP Racing: Premium Engineering

AP Racing CP9660 6-Piston Radi-CAL: The Gold Standard

The CP9660 represents one of the most sophisticated BBK solutions available for the M3 G80:

• Rotor size: 390mm front, 330mm rear options available
• Caliper type: 6-piston fully integrated monobloc (front)
• Pad size: Significantly larger friction area than Brembo systems
• Unique features:
• Radial mounting (Radi-CAL design) reduces flex
• Individual pad wear compensation for balanced friction
• OEM-quality manufacturing with motorsport heritage
• Adjustable pad pressure for fine-tuning pedal feel
• Performance ceiling: Designed for professional track use and competition
• Investment: Premium pricing reflects motorsport-grade engineering

AP Racing CP9668: Alternative Configuration

The CP9668 offers similar engineering philosophy to the CP9660 with slight variations in proportions, useful for specific fitment preferences.

Schaffen: Boutique Excellence

Schaffen CP9660 6-Piston Forged with D8 390mm Rotor

Schaffen brings boutique German engineering to the party:

• Rotor size: 390mm front (largest available for M3 G80), 330mm rear
• Caliper: 6-piston forged construction (higher cost than cast, but superior heat dissipation)
• Rotor technology: D8 design emphasizes maximum cooling geometry
• Ideal for: Track-focused builds where cost is secondary to performance
• Advantages:
• Largest rotor diameter improves thermal management
• Forged calipers rare in aftermarket space
• Exceptional engineering detail
• German TÜV certification typically included

Alcon: Complete Integration

Alcon Superkit for BMW M3 G80

When you want everything dialed in as a complete system:

• Front: 370-390mm options with 6-piston Radi-CAL calipers
• Rear: Matched 330mm setup with 4-piston calipers
• Pads: Alcon's proprietary compounds available
• Rotors: 2-piece construction with aluminum hats
• Advantages:
• Complete system optimization (all components engineered together)
• Exceptional wheel fitment (lower profile calipers)
• Consistent quality across all components
• Strong European availability for quick support

SET Motorsport: Performance-Minded Value

SET Motorsport TX6 6-Piston Street-Focused BBK

For drivers seeking serious performance without excessive complexity:

• Rotor size: 380mm front, 330mm rear
• Caliper: 6-piston monoblock (front)
• Pad options: Street and track compounds available
• Advantages:
• Excellent value proposition
• 6-piston front caliper with modest budget impact
• Good thermal management for mixed-use driving
• Straightforward installation

Recommendation Framework

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4. Brake Pad Selection by Use Case

Choosing the correct brake pads is equally critical to rotor selection. Pads generate friction through chemical composition, each with specific temperature windows where they perform optimally.

Street Driving: Comfort and Safety

Brembo Premium Ceramic Compound

• Operating range: 0-400°C
• Ideal for: Daily commuting, weekend cruises, cold mornings
• Characteristics:
• Low dust generation (reduced wheel staining)
• Excellent cold bite even in winter conditions
• Smooth, linear brake progression
• Reduced brake fade on occasional spirited runs
• Limitation: Performance degrades rapidly above 400°C

NETZSCH NF42

• Operating range: 50-500°C
• Characteristics:
• Minimal noise and vibration
• Very low dust output
• Excellent modulation for everyday driving
• Superior performance compared to ceramic above 350°C
• Sweet spot: Best daily pad for drivers occasionally visiting the track

Street/Track Hybrid Use

Endless MX72

• Operating range: 50-700°C
• Performance envelope: Exceptional
• Characteristics:
• Legendary across Japan and Asia for hybrid use
• Maintains bite even during intense use
• Reasonable dust output
• Excellent pedal feel and modulation
• Stock pad for many performance OEM applications
• Note: Endless pads are increasingly favored by European specialists for their versatility

Pagid RSL1

• Operating range: 50-550°C
• Characteristics:
• German engineering focused on modulation
• Superior braking at 300-500°C (peak performance window)
• Low-temperature performance acceptable for mixed use
• Higher friction coefficient than many alternatives
• Ideal scenario: Driver doing monthly track days who values pedal feel

Dedicated Track Use

Pagid RST3

• Operating range: 150-750°C
• Characteristics:
• Purpose-built for track environments
• Minimal fade across wide temperature band
• Excellent at 500-700°C (typical sustained track temperatures)
• Requires warming up (unsuitable for street use)
• Superior fade resistance than street/track hybrids
• Note: Poor cold bite means these aren't suitable for commuting

Endless CC-Rg

• Operating range: 100-800°C
• Characteristics:
• Exceptional consistency above 400°C
• Maintains friction even during extreme heat cycles
• Slightly higher dust than lower-temperature compounds
• Japanese quality control and reliability
• Performance: Favorite among Nürburgring specialists

Full Race Application

Pagid RS14

• Operating range: 200-800°C
• Characteristics:
• Extreme-duty racing compound
• Minimal fade across entire operating window
• Highest friction available in production form
• Not street-legal in some regions; always verify local regulations
• Requires extensive heating (unsuitable for anything except circuit racing)

Endless CC-R

• Operating range: 200-850°C
• Characteristics:
• The upper boundary of high-performance pads
• Uncompromising friction at extreme temperatures
• Ultimate fade resistance
• Race-only recommendation

Pad Selection Flowchart

```

Your usage pattern:

└─ Pure street driving

└─ Brembo Premium Ceramic or NETZSCH NF42

└─ Occasional track (1-2x/year)

└─ Endless MX72 or Pagid RSL1

└─ Regular track (monthly)

└─ Pagid RST3 or Endless CC-Rg

└─ Competition/frequent racing

└─ Pagid RS14 or Endless CC-R

```

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5. Rotor Considerations and 2-Piece Design Benefits

Size Progression and Thermal Load

The jump from 374mm (stock) to 380-390mm might seem modest, but thermal physics tells a different story:

• Rotor surface area comparison:
• 374mm rotor: ~43,980 mm²
• 380mm rotor: ~45,239 mm² (+2.9%)
• 390mm rotor: ~47,752 mm² (+8.6%)

While percentage increases seem small, remember that rotor temperature scales inversely with cooling surface area. A 390mm rotor can dissipate approximately 15-20% more heat per unit time compared to the 374mm stock system—substantial in thermal management terms.

2-Piece Rotor Advantages

Most modern BBK systems use 2-piece construction: an aluminum center hat with a separate steel friction ring. This design offers significant benefits:

Thermal Benefits

• Aluminum hat (lower coefficient of expansion) allows steel friction ring to expand independently
• Reduces thermal stress and warping potential
• Maintains rotor flatness across wider temperature ranges
• Superior performance during rapid heating/cooling cycles

Weight Reduction

• Aluminum hats weigh approximately 40% less than solid rotors
• Unsprung weight reduction improves suspension response
• Ride quality and handling feel sharper on public roads

Manufacturing Precision

• Steel friction rings maintain tighter tolerances than solid rotors
• Runs with less runout (wobble)
• Contributes to more linear brake progression

Cost Efficiency

• If friction ring wears excessively, replacement costs less than entire solid rotor
• Long-term ownership costs lower

Cross-Drilled vs. Slotted vs. Blank

Cross-Drilled Design

• Small holes through the friction surface
• Improve gas evacuation (outgassing from pads)
• Benefit most visible in wet conditions
• Slight reduction in rotor thickness (minor structural consideration)
• Aesthetic appeal popular with car enthusiasts

Slotted Design

• Slots cut into the surface
• Similar gas evacuation benefits
• Slightly less material removal than cross-drilling
• Offer similar performance benefits with marginally better structural integrity

Blank (Smooth) Design

• Maximum friction surface area
• No material discontinuities
• Slight performance trade-off compared to drilled/slotted
• More durable in extended race applications

Practical recommendation: For the M3 G80, either cross-drilled or slotted designs perform excellently. The choice is primarily aesthetic unless you're in extremely wet conditions where gas evacuation becomes more critical.

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6. Wheel Fitment and Clearance

A common oversight: upgrading brakes without verifying wheel fitment. The M3 G80's wheel options span 19 to 21 inches, and brake calliper size can create interference.

Standard M3 G80 Wheel Sizes

19-inch wheels (most common upgrade choice)

• Excellent fitment with all BBK options listed
• 4-piston systems clear easily; 6-piston systems require verification
• Typically 25-35mm clearance between caliper outer edge and wheel inner surface

20-inch wheels (OEM M Sport/M340i)

• Still adequate clearance for most 6-piston systems
• Verify specific caliper width before purchasing
• Measure your wheel's inner barrel depth

21-inch wheels (rare on G80)

• Tight clearance with 6-piston calipers
• Recommend contacting us before purchasing large-diameter BBK systems
• Some dedicated race systems may require custom wheel selection

Measurement Protocol

Before finalizing your BBK selection, measure:

• Wheel inner barrel depth (distance from wheel mounting surface to inboard edge)
• Wheel bolt hole diameter (should be 72mm for M3 G80)
• Caliper assembly width (available from manufacturer specs)

Contact AME Motorsport with your wheel specifications and desired brake system—our technical team will confirm fitment before you commit to purchase.

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7. European Compliance and Legal Considerations

TÜV Certification

Most BBK systems sold in Europe carry TÜV certification, confirming compliance with EU brake system standards. However, verification is your responsibility.

TÜV Requirements:

• Brake system must provide stopping distances within specified limits (typically 38-40 meters from 100 km/h)
• Brake fluid compatibility confirmed
• Caliper/rotor materials meet metallurgical standards
• Fade resistance within defined parameters

Key point: Not all quality aftermarket brake systems carry TÜV certification. Before purchase, verify that your chosen system includes TÜV documentation.

MOT (UK) Considerations

If your M3 G80 is registered in the UK, MOT testing applies:

• Brake system efficiency: Must meet minimum standards (typically 50% efficiency)
• Pad thickness: Minimum 1.5mm across entire friction surface
• Rotor condition: No cracks, excessive rust, or warping
• Brake fluid: Must be within shelf life (typically 2-3 years)

Quality BBK systems consistently exceed MOT requirements. However, immediately after installation, have your local garage perform a quick safety check to ensure no issues arose during the upgrade process.

German TÜV and Other European Standards

Germany:

• ABE (Allgemeine Betriebserlaubnis) certification preferred
• Many Brembo and Alcon systems carry this

France, Italy, Spain:

• Generally follow EU standards
• Local variation minimal if EU compliance confirmed

Recommendation: Always purchase from vendors who provide TÜV or equivalent certification documentation with your BBK system. AME Motorsport supplies only systems with appropriate certifications.

Circuit-Specific Regulations

If planning to compete or participate in organized track days:

• Nürburgring: Track liability insurance typically requires OEM or certified aftermarket brakes
• Spa-Francorchamps: Similar liability requirements apply
• Brands Hatch: Generally more flexible with aftermarket systems
• Local club events: Varies; confirm with event organizer before upgrading

Most professional BBK systems meet or exceed circuit requirements, but always verify before investing.

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8. Installation Considerations and Support

Professional Installation Recommended

While mechanically straightforward, brake system installation carries safety implications:

• Fluid bleeding: Proper technique prevents air contamination
• Caliper bracket torque: Specific values prevent movement during braking
• Rotor runout: Measurement ensures consistent pad contact
• Brake line routing: Preventing contact with heat sources or sharp edges

Recommendation: Have a qualified BMW technician perform installation. The cost (typically €300-800 depending on system complexity) is worthwhile for peace of mind.

Brake Fluid Upgrade

All modern BBK systems are DOT 4 or DOT 5.1 compatible. For serious track use, consider upgrading to:

Motul RBF 660

• Higher boiling point (660°C) than standard DOT 4 (205°C)
• Significantly reduces brake fade during extended track use
• More expensive but critical for frequent circuit driving

Castrol SRF

• Alternative high-performance option
• Similar benefits to RBF 660
• Slightly higher moisture absorption (requires more frequent changes)

When upgrading fluid, replace the entire system (all four wheels plus master cylinder reservoir). Mixing old and new fluid reduces the high-temperature benefits.

Break-In Period

New brake pads require conditioning:

• Initial 200 km: Gentle driving, no hard braking
• Next 300 km: Progressive brake loads, building temperature gradually
• After 500 km: Full performance available

Rushing this period can compromise pad seating and reduce lifespan. Plan your first track session at least 700 km after installation.

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9. BMW M3 G80 BBK: Performance Benchmarks

Real-World Track Data

To contextualize the improvements, consider typical data from Nürburgring track days:

Stock Brakes vs. Brembo GT-R vs. AP Racing CP9660 Note: These figures come from driver feedback and thermal imaging data. Individual results vary based on driving style, ambient conditions, and pad selection.

Cost vs. Performance Analysis

Value recommendation: The Brembo GT-R offers exceptional performance for the investment, particularly for drivers doing 4-12 track days annually.

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10. Frequently Asked Questions

Will a big brake kit affect my daily driving?

Short answer: No, positively.

A quality BBK actually improves daily driving through more progressive brake feel and reduced fade during normal driving. The only potential downside—increased dust from performance pads—is manageable by choosing street-appropriate compounds like Brembo Premium Ceramic.

What's the lifespan of brake pads and rotors?

Pads: 25,000-40,000 km for street use; 10,000-15,000 km for track use Rotors: 80,000-120,000 km for street use; highly variable for track (depends heavily on pad choice and thermal cycling)

Track-dedicated pads wear faster because they're engineered for friction at high temperatures, not mileage. This is intentional—maximum track performance requires accepting faster wear.

Can I mix rotor sizes (e.g., 390mm front, 370mm rear)?

Not recommended. Brake systems should be proportional. Mismatched sizes can cause uneven brake bias, making the vehicle pull to one side under hard braking. Stick with manufacturer-matched sets.

Are drilled rotors weaker than solid rotors?

In theory, any material removal reduces structural strength. In practice, quality drilled rotor designs are extensively tested and perform identically to solid rotors under normal use. The small performance benefits (gas evacuation) are worth the negligible strength trade-off.

What's the difference between monoblock and floating calipers?

Monoblock (fixed) calipers:

• Single rigid casting
• Pads mounted on fixed carrier
• Less flex under pressure
• Better precision and modulation
• More expensive to manufacture

Floating calipers:

• Pads on sliding carrier
• Allows thermal expansion accommodation
• Simpler design, lower cost
• Still perfectly adequate for street and occasional track

For the M3 G80 at track speeds, monoblock 6-piston front calipers are ideal, but well-engineered floating rear calipers are perfectly sufficient.

My M3 has optional carbon ceramic brakes. Should I upgrade?

The factory carbon ceramic system is genuinely excellent—possibly the best stopping system from the factory. However, if you're tracking the car regularly, standard BBKs with appropriate pads often outperform carbon ceramic because:

• Carbon ceramics require extended warm-up periods
• Stainless steel rotors with ceramic pads achieve superior performance at race temperatures
• Cost savings from avoiding ceramic are substantial

Verdict: Stick with your ceramic brakes if you have them. They're exceptional. But don't feel obligated to buy them if specifying a new vehicle—a Brembo GT-R system is arguably superior for track use.

I want the biggest brakes possible. What's the maximum rotor size I can fit?

For the M3 G80, the practical limit is 390mm front rotors. Larger rotors (400mm+) may create wheel fitment issues and offer minimal additional benefit. The 390mm Schaffen system represents the maximum practical upgrade.

Is a BBK worth the investment if I only do occasional track days?

Yes. Even one track day per year benefits from a BBK. The improved consistency and fade resistance translate to safer driving, better brake feel, and more enjoyment. Think of it as a safety investment, not purely a performance upgrade.

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11. Installation Process Overview

Timeline and Labor

Professional installation: 3-4 hours Parts delivery: 2-3 weeks (subject to current stock) System break-in period: 700 km before full track use

What's Included in a BBK System

• Calipers (front and rear)
• Rotors (usually 2-piece construction)
• Caliper bracket and hardware
• Stainless brake lines (where applicable)
• Pad wear sensors (if applicable)

What You'll Need Separately

• Brake pads (choose per your use case)
• Brake fluid upgrade (recommended)
• Professional installation labor
• DOT 4/5.1 compatible fluid (fill system after bleeding)

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12. Next Steps: Choosing Your M3 G80 BBK

Selecting the right brake system requires balancing several factors:

• Budget allocation: Entry-level (€2,200) to premium (€6,000)
• Usage pattern: Street-only, occasional track, frequent track, competition
• Wheel fitment: Confirm clearance before purchasing
• Climate: Cold winters demand different pad selection than Mediterranean heat
• Support requirements: Aftermarket or factory-backed supplier

Quick Decision Framework

If you answer "yes" to:

• "Will I track my M3?" → Consider Brembo GT-R minimum
• "Will I track frequently (monthly)?" → Invest in AP Racing or Schaffen
• "Is cost primary concern?" → SET Motorsport TX6 offers excellent value
• "I want everything optimized together?" → Alcon Superkit integration approach
• "I want the absolute best available?" → Schaffen CP9660 with D8 rotor

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13. AME Motorsport: Your BBK Specialist

At AME Motorsport, we understand that brake system selection is deeply personal. We've equipped hundreds of M3 G80s with BBK systems across Europe and beyond.

Why Choose AME Motorsport

✓ Expert knowledge: Our team understands BMW platform-specific considerations

✓ Global shipping: We service European, UK, and international customers

✓ Genuine products: All systems are authentic, TÜV-certified where applicable

✓ Technical support: Free consultation on fitment, compliance, and pad selection

✓ Quality assurance: Every system checked before dispatch

✓ Trusted brands: We partner exclusively with Brembo, AP Racing, Schaffen, Alcon, and SET Motorsport

Getting Started

Step 1: Visit our BBK collection Step 2: Select your vehicle (BMW M3 G80) Step 3: Choose your system (Brembo, AP Racing, etc.) Step 4: Contact our technical team with your wheel specifications Step 5: Confirm fitment, arrange installation support

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Conclusion

The BMW M3 G80 is an exceptional performance platform. Its power delivery and agility deserve equally impressive stopping capability. While factory brakes serve adequately for everyday driving, serious enthusiasts—particularly those exploring European circuits—quickly discover that a big brake kit transforms the complete ownership experience.

Whether you choose the excellent value of a Brembo GT-R system, the integrated approach of Alcon's Superkit, or the ultimate performance of AP Racing's CP9660, upgrading your M3 G80's brakes is one of the highest-ROI modifications available.

The choice isn't between "factory brakes are good enough" or "I need an upgrade." Rather, it's about defining your driving ambitions and selecting the system that matches your goals.

Ready to transform your M3's stopping power? Browse AME Motorsport's BMW M3 G80 BBK Selection

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Specification Quick Reference

BMW M3 G80 Factory Brake System:

• Front: 374mm ventilated disc, multi-piston compound caliper
• Rear: 370mm ventilated disc, floating caliper
• Pads: Brembo performance compound (0-400°C)
• Weight: ~1,730 kg

Recommended BBK Sizes:

• Front: 380-390mm
• Rear: 330mm (proportional to front)

Street Pad Recommendations:

• Brembo Premium Ceramic (0-400°C)
• NETZSCH NF42 (50-500°C)

Track Pad Recommendations:

• Endless MX72 (50-700°C)
• Pagid RSL1 (50-550°C)
• Pagid RST3 (150-750°C)
• Endless CC-Rg (100-800°C)

European Compliance:

• TÜV certification required
• MOT testing (UK)
• ABE certification preferred (Germany)

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Article published: February 2026 For updated pricing and availability, visit AME Motorsport Questions? Contact our technical team: AME Motorsport Customer Support