Forge Motorsport dump valve for Ford Fiesta VIII (MK8) ST and Puma ST

Forge Motorsport has developed a dump valve solution for the Ford Fiesta ST Mk8 and Ford Puma ST, which were factory-supplied without an original valve.

As the engine does not have a factory-fitted diverter valve, this kit uses a Forge dual-piston valve. When the throttle is released, it produces a distinctive sound while improving throttle response during gear changes by reducing turbo lag. It helps the turbocharger maintain its rotational speed and readiness for renewed acceleration, while reducing rotor load. This is particularly important on tuned and otherwise modified vehicles.

The kit includes two different spring rates for standard boost pressure settings and Stage 1. Additional springs are also available for Stage 2 and higher settings, including options for hybrid turbocharger conversions.

The kit includes all the required hardware and detailed step-by-step instructions, so installation with suitable garage tools can also be carried out at home in approximately a few hours.

The kit includes:

• 1 × FMDV35 valve with yellow spring
• 1 × 0.5 m vacuum hose with a 4 mm diameter
• 1 × vacuum connector
• 3 × hose clamps
• 1 × coupling made from CNC-machined aluminium billet
• 5 × cable ties
• 1 × uprated blue spring
• 1 × dedicated silicone hose

• CNC-machined aluminium couplings and components
• CNC-machined Forge dual-piston valve
• The silicone hoses have an inner lining made from modified silicone, known as fluorosilicone. They are suitable for modern long-life coolants, organic acid technology (O.A.T.) coolants and air containing oil mist.
• The hose construction exceeds the properties of the original hoses and improves the technical and visual appearance of the engine bay.
• The Forge valve does not trigger the engine malfunction light (EML).

Suitable for: Ford Fiesta VIII (MK8), Ford Puma II (J2K).

Compatible vehicles (manufacturer data)

Before ordering, check that the product matches your vehicle (model, year and engine). If in doubt, write to us — we will check for you.