Stone Exhaust Mercedes-Benz M274 C238 Cat-Back Valvetronic Exhaust System for E-Class Coupe E250 and E300 2017+ UK
Unlock the sound and response your Mercedes-Benz deserves with the Stone Exhaust Valvetronic Cat-Back Exhaust System for the C238 E-Class Coupe E250 and E300 with the M274 engine. Engineered for precise OEM fitment using 3D scanning and reverse engineering, this cat-back exhaust delivers a deeper, sportier tone with on-demand valve control, refined daily drivability, and quality that stands out on and off the road. Part Number: MP518BS.
If you are searching for a Mercedes-Benz C238 E-Class E250 exhaust, E300 exhaust, M274 cat-back, valved exhaust, valvetronic exhaust, performance exhaust upgrade, catback exhaust for E-Class Coupe, Stone Exhaust UK, OPF delete compatible exhaust, or plug and play OBDII valve control for Mercedes, this is the perfect solution.
Why choose Stone Exhaust for your Mercedes-Benz C238 E-Class
- Designed specifically for the Mercedes-Benz C238 E-Class Coupe E250 and E300 with the M274 engine, including M274 4Matic variants
- Valvetronic cat-back exhaust system with remote control for ON, OFF and AUTO valve modes
- Plug and play OBDII controller for effortless valve operation and automatic RPM-based opening in AUTO mode
- One piece design with true OEM-level fitment achieved via 3D scanning and reverse engineering of the factory system
- Eliminates unwanted cabin drone for comfortable motorway cruising
- Engineered with precision mechanical welding and direct spot welding for strength and reliability
- Developed in house with 7 axis CNC bending for optimal flow and accuracy
- Refined Stone signature exhaust note with valves open, subtle and refined with valves closed
Real-world results that drivers love
We have supplied and used Stone Exhaust systems on customer cars and in our own projects at Nforcd. Feedback is consistently positive: a premium valved exhaust note when you want it, quiet comfort when you need it, excellent fitment, and superb build quality. The Valvetronic control gives you the perfect balance between daily usability and performance sound.
Valvetronic control made easy
The included remote offers three modes: ON for full sound and performance, OFF for quiet operation, and AUTO to open the valve automatically at a preset RPM. The system is plug and play via the OBDII port, so setup is quick and clean without complicated wiring.
OPF delete option for OPF-equipped cars
Stone offers an OPF delete that can be included free of charge. This enables installation of the Stone cat-back on OPF-equipped vehicles without triggering an error code, removing the need to code out OPF faults on the ECU.
Engineered for precision and durability
- 3D scanning and reverse engineering of the OEM exhaust for 100 percent OEM fitment
- 7 axis CNC bending achieves exceptional roundness and flow consistency
- Crisscross and overlapping welding techniques increase weld penetration and strength
- Direct spot welding by mechanical arms for repeatable, high-precision joins
Installation and fitting
Direct replacement cat-back with OEM-style fitment points. The Valvetronic control is plug and play via the OBDII port and can be installed in minutes. For professional installation and a seamless experience, we recommend fitting at Nforcd in Warwickshire. Request a fitting quote via Sales@nforcd.com.
Compatibility
Mercedes-Benz E-Class Coupe C238 with M274 and M274 4Matic engines:
- C238 E250 2017+
- C238 E300 2017+
Part number
MP518BS
Warranty
Stone Exhaust 2 year warranty.
Video
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