Alfa Romeo 4C Helmholtz Exhaust
This is a custom tuned Alfa 4C exhaust system with Helmholtz resonator. It is a straight through system and uses a resonator and tuned pipe diameters to remove the drone at around 70-80mph.

The Helmholtz Chamber design is the only proven effective way to kill drone in the Alfa Romeo 4C. If you want a true sport tuned Euro sound for your 4C and no drone, this is it. It gives the 4C some of that classic Alfa Romeo exhaust note that Alfisti love.

We have 2 versions! — 1) The latest version uses the Quicksilver Sound Architect updated with remote valve switching to run through the resonator, or non resonated exit. Decide which mode you want with the touch of a button on your mobile phone. Included remote wiring can be hardwired and tucked out of the way. Watch this video for more details about the Quicksilver Sound Architect system.

This system also includes carbon tips which can be angled to suite your preference, and provide a nice detailed carbon fiber accent to the back of the Alfa Romeo 4C. 

Weight of the system with resonator is only 3.3 lbs. heavier than Alfa's race system. Easy installation retains the factory exhaust exits, and it's compatible with both the 4C Coupe and Spider. Clamps are included. See the Video.

— 2) The original non-switchable version, provides amazing sound and performance at an unbeatable price point. This version also includes the carbon tips, and the proven Helmholtz drone reduction.

The fit and finish produced by Quicksilver UK is superb and what you’d expect for a car of the 4C’s level. 

Alfa Romeo 4C factory Mid-Pipe
If your 4C has a modified mid-pipe, you will need to restore it to OEM spec to fit the Helmholtz system. Select that option, shipping is included — Lower 48 states only.