Cure the rasp and unlock the rich, balanced sound of your BMW F8X M3 or M4's S55 with the Valvetronic Designs equal-length valved cat-back, an equal-length 2.75" mid-section with H-pipe and a 3.5" axle-back in T304 stainless steel or Grade 5 titanium.
The S55 in the F8X M3 and M4 is a performance masterpiece, but its stock exhaust note has long been criticised for excessive rasp and a lack of tonal depth. This equal-length valved cat-back eliminates the factory harshness and unlocks the rich, balanced sound the S55 was always capable of producing.
The system features a 2.75-inch equal-length mid-section with an H-pipe feeding into a 3.5-inch axle-back. The equal-length design smooths the exhaust tone across the rev range while preserving the aggressive character owners love. With the valves open, gases exit freely from the passenger-side tips for maximum volume and performance. With the valves closed, flow is routed through the quad-chamber muffler to the driver-side tips for a quieter, more refined note, ideal for daily driving. No cutting or welding is required; this is a true direct bolt-on system designed to mount to factory points.
Why it works
- Equal-length mid-section: balances pulses for a cleaner, smoother tone without losing aggression
- H-pipe design: improves scavenging for a fuller, more refined sound
- Dual-mode operation: raw and loud (open) or subdued and civilised (closed)
Sound and control
- Valves open: aggressive, free-breathing tone with reduced rasp and improved high-rpm clarity
- Valves closed: stock-like sound levels for stealthy driving
- Electronic valve control: includes a standalone controller; OEM integration available
Construction and options
- Materials: T304 stainless steel or Grade 5 titanium
- Weight savings: –21.7 lb (stainless) / –49.2 lb (titanium) vs OEM
- Craftsmanship: precision TIG welds and fully mandrel-bent tubing for maximum flow
- Tips: multiple premium finish options to complement your M3 or M4
Fitment
- 2015–2018 BMW M3 (F80)
- 2015–2020 BMW M4 Coupe (F82)
- 2015–2020 BMW M4 Convertible (F83)
Installation
- Direct bolt-on; no cutting or welding required
- 100% reversible, return to stock at any time
- Note for S55 owners: on free-flow/race downpipes, "2k rpm rasp" may be present during low-rpm shifts. For the most refined tone, we recommend high-flow (200 cell) catalytic converters
What's included
- 2.75" equal-length H-pipe mid-section
- 3.5" axle-back with quad-chamber muffler
- Electronic valve system with controller (OEM integration optional)
- All necessary clamps and hardware
Specifications
- Mid-section diameter: 2.75" equal-length with H-pipe
- Axle-back diameter: 3.5"
- Material: T304 stainless steel or Grade 5 titanium
- Valves: electronic, rapid open/close
- Weight savings: –21.7 lb (stainless) / –49.2 lb (titanium) vs OEM
- Design: quad-chamber muffler for refined closed-valve tone
Why buy from Vero Motorsport
Vero Motorsport is an authorised Valvetronic Designs dealer, with fast Australia-wide shipping and expert support before and after your purchase.
Order online today and add the F8X M3 / M4 valved cat-back to your cart.
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Not sure if a part fits your vehicle? Contact us with your make, model, and year before ordering. We will confirm compatibility so you order the right part the first time.
Every product is covered by a 12-month manufacturer-backed warranty from the date of purchase.
Vero Motorsport works with a national network of authorised installers. Contact us with your location and fitment requirements for a recommended workshop in your area.
