How to Choose the Suitable Vacuum Braking System for the Electrification Conversion of VW T2
Converting a beloved VW T2 to electric power is a rewarding but intricate process. One of the most crucial aspects of this conversion is ensuring that the braking system remains safe and effective. Traditional VW T2s rely on engine-generated vacuum to power the brake booster, enhancing braking performance with minimal pedal effort. However, electric vehicles (EVs) lack this natural vacuum source. Therefore, choosing the suitable vacuum braking system is imperative for maintaining optimal braking in your electrified VW T2. Here’s a comprehensive guide to making the right choice.
- Understanding the Vacuum Requirement in EV Conversions
In an ICE vehicle, the engine creates a vacuum that assists the brake booster, reducing the force needed to apply the brakes. When converting to electric power, this vacuum source disappears. Without proper supplementation, the brake pedal becomes extremely stiff, compromising safety. Thus, an artificial vacuum source—typically an electric vacuum pump system—is essential.
- Types of Vacuum Braking Solutions
Two main options exist for vacuum braking in EVs:
- Electric Vacuum Pump with Reservoir:This system uses an electric pump to create vacuum, stored in a reservoir. The vacuum then powers the original brake booster. This solution is straightforward, cost-effective, and preserves the stock brake feel.
- Electric Brake Booster (Vacuum-less):This advanced system replaces the traditional booster with an electrically actuated unit. It eliminates the need for vacuum but requires more complex integration and often a higher budget.
For most VW T2 conversions, the electric vacuum pump system is preferred due to its compatibility and simplicity.
- Key Factors for Choosing a Vacuum System
- Compatibility with VW T2 Setup:
Ensure the vacuum pump and reservoir can be integrated with the existing brake booster and master cylinder. The VW T2’s compact space may require careful planning for mounting the components. - Pump Specifications:
- Voltage:Match the pump to your EV’s auxiliary 12V system.
- Vacuum Capacity & Flow Rate:Select a pump capable of achieving and maintaining the necessary vacuum level (usually 18-22 inHg) for your brake booster. A higher flow rate ensures quicker vacuum recovery.
- Duty Cycle:Choose a pump designed for frequent or continuous operation, as EVs may cycle the pump more often than ICE vehicles.
- Vacuum Reservoir Size:
The reservoir should store enough vacuum for multiple brake applications. For a VW T2, a 1–1.5-liter reservoir is typically adequate. This prevents the pump from running constantly and provides backup in case of pump failure. - Noise and Vibration:
Opt for a low-noise, low-vibration pump to maintain the quiet EV driving experience. Use rubber mounts to dampen noise transmission into the cabin. - Durability & Environmental Protection:
Select a pump with a high ingress protection rating (IP67 recommended) to withstand moisture, dust, and road grime. Reliable brands like Bosch, ATE, or Girling are often used in conversions. - Control System & Sensors:
The vacuum system should include a pressure sensor and relay to automatically control the pump, activating it when vacuum drops below a set threshold. Integration with your EV’s control system allows for diagnostics and monitoring. - Safety Redundancy:
Ensure there is redundancy—a large reservoir or backup pump—so that even if the pump fails, you still have some assisted braking capability. - Installation and Integration Tips
Plan the mounting location for the pump and reservoir, ensuring easy access and protection from road hazards. Route vacuum lines and electrical wiring away from heat sources and moving parts. Confirm that your 12V auxiliary battery can handle the additional load without significant drain.
- Real-World Suitability for VW T2
The electric vacuum pump system is most suitable for VW T2 conversions, offering effective braking assistance while retaining the original brake setup and pedal feel. It is also more economical and easier to source and maintain.
- Testing and Validation
After installation, conduct thorough testing. Verify vacuum build-up time, pedal feel under various conditions, and system response with and without the pump. Regularly inspect for leaks and ensure the system maintains vacuum over time.
Conclusion
Choosing the right vacuum braking system is essential for safety and performance in your electrified VW T2. By selecting a robust electric vacuum pump solution compatible with your vehicle’s braking system, you ensure responsive, reliable braking that meets modern standards. This allows you to enjoy your classic T2’s timeless charm with the efficiency and smoothness of electric power, all while driving with confidence and peace of mind.
