• boost characteristics specific turbo system 50mm valve provides fast
  • The Viper combines a 50mm high-flow valve with externally adjustable spring preload
  • Series Adjustable Atmospheric Turbo Blow-Off Valve 540198
  • Blow Off Valves BOV New Products Engine/Drivetrain Turbo System
  • vent-to-atmosphere blow-off valve affect drivability some mass-airflow-metered vehicles because
  • turbo boost setup rather relying one fixed calibration
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Granatelli Motor Sports

Granatelli 50mm Viper Series Adjustable Atmospheric Turbo Blow-Off Valve – 540198

Granatelli 50mm Viper Series Adjustable Atmospheric Turbo Blow-Off Valve – 540198

SKU:'540198

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GRANATELLI VIPER SERIES

FAST PRESSURE RELEASE, ADJUSTABLE RESPONSE — AND YES, IT MAKES THE RIGHT NOISE.

The Granatelli 540198 Viper Series 50mm Blow-Off Valve is a high-flow vent-to-atmosphere turbo BOV designed for street, street/strip and race applications.

Its adjustable spring preload lets the valve response be tailored to the vacuum and boost characteristics of the specific turbo system, while the 50mm valve provides fast pressure relief when the throttle closes.

50MM
High-Flow BOV 		ADJUSTABLE
Spring Preload 		ATMOSPHERIC
Vent-to-Atmosphere

What Makes the Viper Different?

The Viper combines a 50mm high-flow valve with externally adjustable spring preload. This allows the blow-off valve response to be fine-tuned to the engine’s vacuum characteristics and turbo boost setup rather than relying on one fixed calibration.

Is the Viper Right for Your Setup?

GOOD FOR
• Turbo street cars
• High-boost builds
• Drag and race cars
• Adjustable BOV setups
• Vent-to-atmosphere systems		 VERIFY FIRST
• Atmospheric venting compatibility
• BOV mounting flange
• Vacuum reference source
• Engine-management strategy
• Available charge-pipe space

Product Specifications

Part Number 540198
Product Type Turbo Blow-Off Valve
Valve Size 50mm
Discharge Style Vent-to-Atmosphere
Adjustment Adjustable Spring Preload
Construction Billet Aluminum
Fitment Universal Custom Turbo Applications
MAF VEHICLE NOTE: A vent-to-atmosphere blow-off valve can affect drivability on some mass-airflow-metered vehicles because previously measured air is released from the charge system. Verify your engine-management configuration before installation.

Key Features & Benefits

  • Application-focused Granatelli Motor Sports design
  • Built for dependable performance and service
  • Designed for enthusiasts, professional installers, and performance builds

Fitment & Installation

Confirm the part number, vehicle or engine application, dimensions, and supporting components before installation. Modified vehicles may require additional clearance, fabrication, calibration, or related hardware depending on the combination.

Frequently Asked Questions

What does a blow-off valve do?
A blow-off valve releases excess charge pressure when the throttle closes, helping manage pressure in the intake tract.

Will this work on a modified vehicle?
Compatibility depends on the complete vehicle combination. Confirm the listed application and supporting components before installation.

Why Choose Granatelli Motor Sports?

Granatelli Motor Sports develops performance components for real-world street, street/strip, race, and custom applications, with an emphasis on practical performance, dependable construction, and integration into serious automotive builds.