GrimmSpeed Exhaust Valve Defeat Module – 2015+ Ford Mustang Shelby GT350 / GT350R | Voodoo 5.2L

Unlock the full sound and exhaust flow potential of your 2015+ Ford Mustang Shelby GT350 or GT350R's Voodoo 5.2L flat-plane V8 with the GrimmSpeed Exhaust Valve Defeat Module. The GT350's active exhaust valve system restricts exhaust flow in its quieter operating modes — limiting the full acoustic character and exhaust flow of the Voodoo engine. GrimmSpeed's defeat module overrides the factory exhaust valve control to keep the valves open at all times, delivering maximum exhaust flow and the full, unrestricted sound of the Voodoo 5.2L flat-plane V8 on demand. Simple plug-and-play installation — no cutting, splicing, or permanent modifications required.

Key Features

• Defeats Active Exhaust Valve Control: Overrides the factory exhaust valve control system to keep the GT350's active exhaust valves open at all times — eliminates the flow restriction and sound suppression of the factory quiet modes
• Maximum Exhaust Flow & Sound: With valves held open, the Voodoo 5.2L flat-plane V8 delivers its full, unrestricted exhaust note and maximum exhaust flow at all times
• Plug-and-Play Installation: Simple electronic module that plugs into the factory exhaust valve wiring — no cutting, splicing, or permanent modifications to the vehicle's wiring harness required
• GT350 & GT350R Compatible: Fits both the standard Shelby GT350 and the track-focused GT350R variants of the S550 Mustang
• GrimmSpeed Quality: Manufactured by GrimmSpeed — a trusted name in performance parts engineering

Specifications

• Type: Exhaust Valve Defeat Module
• Operation: Keeps active exhaust valves open at all times
• Installation: Plug-and-Play (no permanent wiring modifications)
• Engine: Ford Voodoo 5.2L Flat-Plane V8
• Fitment: 2015+ Ford Mustang Shelby GT350 / GT350R (S550)
• Part Number: 070044

Note: Keeping exhaust valves open at all times will result in a significantly louder exhaust note at all times, including at idle and low speeds — consider local noise ordinances and track regulations before use. Reversible — the module can be unplugged to restore factory exhaust valve operation. Professional installation recommended.