Innovators West | Nissan RB "STX" Harmonic Damper

Innovators West Street Extreme (STX) Harmonic Balancer – Nissan RB – 30mm Standard Crank Snout

Part Number: RBMP-STX

Control crankshaft harmonics and complete your Nissan RB front-drive system with the Innovators West Street Extreme (STX) Harmonic Balancer, designed specifically for RB engines using the standard 30mm crankshaft snout.

In a performance engine, combustion pressure causes the crankshaft to twist and recover repeatedly during operation. These torsional movements can place additional stress on the crankshaft, bearings and rotating assembly, particularly as engine speed, boost and cylinder pressure increase.

Innovators West uses a combination of spring-loaded inertia rings and wet-friction clutch damping technology to absorb and manage these torsional vibrations across a broad operating range. Internal fluid lubricates the damping assembly while also helping transfer heat into the outer housing, supporting consistent performance in demanding street and motorsport applications.

The STX provides the standard-snout option in the Innovators West Nissan RB range and is supplied with the required accessory-drive components for the alternator, water pump and air-conditioning system.

Features & Benefits

• Innovators West Street Extreme (STX) model
• Designed specifically for Nissan RB engines
• Suits standard 30mm RB crankshaft snout
• Helps control crankshaft torsional vibration
• Spring-loaded inertia ring damping system
• Wet-friction clutch technology
• Internal fluid lubrication
• Internal fluid assists with damping-system heat transfer
• Designed for street, performance and competition applications
• Includes alternator and water-pump drive pulley
• Includes air-conditioning drive provision
• Optional power steering pulley available separately
• Designed as a complete front-drive solution for standard-snout RB builds

Technical Specifications

• Product Type: Harmonic Balancer
• Brand: Innovators West
• Model: Street Extreme (STX)
• Part Number: RBMP-STX
• Engine Family: Nissan RB
• Crankshaft Snout Diameter: 30mm
• Damping System: Spring-Loaded Inertia Ring / Wet-Friction Clutch
• Alternator Drive: Included
• Water Pump Drive: Included
• Air Conditioning Drive: Included
• Power Steering Pulley: Sold Separately
• Application: Street / Performance / Motorsport

What’s Included

• 1 × Innovators West Street Extreme (STX) Harmonic Balancer
• Integrated / supplied air-conditioning drive
• Water pump / alternator drive pulley

Sold Separately

• Innovators West Power Steering Pulley

Pulleys & Accessory Drive

The STX balancer is supplied with the drive components required to operate the alternator, water pump and air conditioning, making it a practical option for performance RB builds that retain factory-style accessories.

For engines retaining power steering, the additional Innovators West power steering pulley is required.

Where both power steering and air conditioning are being retained, the air-conditioning belt can be driven from the balancer. Alternatively, Platinum Racing Products recommends using its AC relocation kit, which allows the power steering and air-conditioning drive to be configured from the same power-steering pulley arrangement.

This gives builders flexibility to configure the front accessory drive around the intended vehicle use and engine layout.

Applications

• Nissan RB-series engines
• RB26 performance builds
• RB25 applications where compatible
• RB30-based combinations using a standard 30mm crank snout
• High-performance street cars
• Drag racing applications
• Circuit and competition engines
• Turbocharged RB combinations
• Custom RB engine conversions

Why Harmonic Control Matters

Every combustion event applies a torsional load to the crankshaft.

Rather than rotating as a completely rigid component, the crankshaft twists and rebounds under load. As engine output and RPM increase, these torsional vibrations can become more severe and may contribute to additional loading on the crankshaft, bearings and other rotating components.

A properly matched harmonic balancer helps absorb and control this energy, reducing the amount of damaging vibration transmitted through the rotating assembly.

Innovators West Wet-Friction Technology

Innovators West dampers use spring-loaded inertia rings combined with a wet-friction clutch system to manage crankshaft torsional vibration.

Internal fluid lubricates the damping components while helping transfer heat into the damper housing. This allows the system to continue working across a wide operating range rather than relying on a single narrow harmonic frequency.

The result is a damper suited to the changing RPM and load conditions encountered in serious performance engines.

Important Fitment Note

The RBMP-STX is designed for Nissan RB crankshafts using the standard 30mm crankshaft snout.

For engines using the larger 35mm crankshaft snout found on PRP-supplied Callies RB crankshafts, select the Innovators West Race Extreme (RACEX) Harmonic Balancer instead.

Always confirm crankshaft snout diameter and accessory-drive configuration before ordering.

Why Choose Innovators West?

Innovators West manufactures premium harmonic dampers and accessory-drive components for high-performance street and motorsport applications.

The STX provides a purpose-designed solution for conventional Nissan RB crankshaft configurations while retaining the accessory-drive functionality required by many street and competition builds.

Why Buy From Prime Speedworks

Prime Speedworks supplies Innovators West harmonic dampers, pulleys, installation tooling and supporting hardware to racers, engine builders and performance workshops throughout Australia.

Whether you're building a street-driven RB with full accessories or a dedicated race combination, Prime Speedworks can help match the correct damper, power-steering pulley, balancer hardware and accessory-drive components to your setup.