Flap control

Vacuum-controlled stainless steel valve actuation: Sound & performance at the push of a button

In modern exhaust system design, valve control is the ultimate tool for striking the balance between everyday comfort and unfiltered motorsport sound. Whether building a custom performance exhaust system from scratch or upgrading an existing system: A high-quality, vacuum-controlled exhaust valve enables precise control over your vehicle’s exhaust flow and acoustics.

At Turbo-Parts.de, you’ll find exhaust valves and control systems made of high-strength, corrosion-resistant stainless steel, specifically designed to meet the demanding requirements of the tuning and motorsports sectors.

How does a vacuum-controlled valve system work?

The system operates purely pneumatically: an external vacuum source (e.g., directly from the engine’s intake tract or an electric vacuum pump) actuates an actuator on the exhaust valve. As soon as vacuum is applied, the diaphragm in the actuator retracts and, via a linkage, actuates the valve in the pipe.

For the custom design of your exhaust system, two basic approaches are available:

• Normally Open (NO): Without vacuum pressure applied, the valve remains fully open due to an internal spring (motorsport mode). Only when vacuum pressure is applied (e.g., at idle or while cruising), does the valve close to drastically reduce the noise level.

• Closed at rest (Normally Closed - NC): Here, the mechanical spring ensures that the valve is closed by default (Quiet Mode). As soon as the control system releases vacuum, the system opens instantly and allows maximum exhaust flow.

Convenient tuning: Flap control via radio remote

Our intelligent wireless control kits ensure maximum control from inside the cabin. Using a compact remote control or an integrated wireless module, you can conveniently open or close the exhaust flaps manually right from the cockpit. The system controls an electronic solenoid valve that precisely releases or blocks the vacuum. This allows you to switch between a subtle stock sound and a brutal racing sound in a fraction of a second.

Designed for professionals: Highest material quality & standard diameters

Building a high-end exhaust system requires components that make no compromises. Our flap controls are precisely designed for professional welding and workshop use:

• Premium stainless steel: The housing, flap blade, and mechanical linkage are made of heat-resistant and rust-proof stainless steel. They withstand extreme exhaust gas temperatures (EGT) as well as salt and moisture over the long term.

• Precise fit for welding: The valves feature clean, precisely machined connection edges and can be seamlessly welded into your pipes using the TIG or MIG process.

• All standard diameters: We supply exhaust flaps in the pipe diameters most commonly used in tuning — from compact 60 mm (2.36 inches) to the classic 63.5 mm (2.5 inches) and 70 mm (2.75 inches), all the way up to the large 76 mm (3-inch) and 89 mm (3.5-inch) systems for extreme turbo projects.