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Stone Exhaust
This Downpipe is often purchased with the Stone Exhaust Mercedes-Benz AMG W/C/S205 C63S Cat-Back Valvetronic Exhaust System
Description
Meet the latest patented technology that adheres to the world's increasingly stringent environmental regulations, at the same time enhances performance to another level. In comparison to commercially available linear frustums, the "eddy catalytic technology" adopts an arc-packaging method. The turbine emissions process produces a vortex effect which purifies the exhaust gases while maintaining an equal amount of back pressure. When compared to a variety of conventional straight downpipes, the patented eddy catalytic technology can effectively increase horsepower and torque.
In the lower rpm you will be immerse with vast amount of torque until you reach higher rpm where the vortex effect really comes to life and opens up the Catalytic, resulting in a performance similar to a 100 CELL Catalytic. However in the lower rpm, the catalytic will produce efficient and clean emission similar to a 400CEL Catalytic and produce no Check Engine Lights, completely error free.
Power Gain
|
POWER + 6.81Ps at 5706rpm |
TORQUE |
Features
Fitted Photos





R&D and 3D Scanning
Stone Exhaust engineers use reverse engineering by 3D scanning OEM parts to understand their functionality and identify weaknesses. Data has been collected continuously in order to analyse factors such as pipe diameter, route and degrees of the bending angles of the M177 downpipe.
During R&D, Stone Exhaust utilises the 3D simulation software to stimulate the exhaust gas flow movement, thermal and pressure rise zone. Progressive improvements were continually made until the optimal performance was achieved.

7 Axis CNC Bending Machine
Stone Exhaust System are constructed utilising a 7 axis CNC Bending Machine which is the ultimate machine for high levels of precision delivery, necessary for industries such as the aerospace and defence industries.
With the state-of-the-art bending machine, Stone Exhaust has achieved the world leading industry’s standard to an impressive 98% roundness, whilst maintaining the wear of the outer bore at only 25% at 180°. Airflow obstruction and welding fracture problems are prevented by utilising this technology. With the combination of the CNC Bending machine, Reverse Engineering and 3D Design Scanning, Stone exhaust has created an integrally moulded exhaust pipe with an accuracy error of less 0.025mm.

Crisscross and Overlapping Welding Technique
The flange between the turbo and the downpipes reaches extreme temperatures (800? to 1100?) which creates stress on the connection point. By utilising both welding techniques to increases the width and penetration of welds. This increases the endurance and tolerance of these connection points, leading to quality products with reliable performance.

Direct Spot Welding
Our highly skilled engineers perform direct spot welding to increase product strength. This is undertaken by industry leading mechanical welding arms, proven to achieve greater precision and penetration in their welds compared to manual welding, resulting in an end product that is a work of art.

Art of Welding

Compatibility - M177 Engine
Mercedes-Benz
C-Class
(7G/9G/9G with GPF)
Compatibility Check
To ensure the part(s) you have ordered fits your vehicle, we run a compatibility check prior to dispatch. We can do this either using your license plate or the last 7 digits of your VIN. Simply enter your car details prior to checkout.
Warranty
Stone Exhaust 2 Year Warranty
Manufactured by
Stone Exhaust
Part Number
M217E (7G)
M217NE (9G without GPF)
M217NEG (9G with GPF)

We are committed to giving you the best price. if you find a lower price on the same item at an eligible UK retailer website, we will match it.
For in-stock item, get guaranteed next day UK delivery. Same day dispatch available on in-stock items if your order is placed before 1pm UK Time.
We ship worldwide via DHL International, simply enter your full address at checkout to see the shipping option(s) and quote(s). Same day dispatch available if your order is placed before 1pm UK Time on all in stock items!