The T9388 is the latest addition to the DV+ range of diverter valves from GFB (Go Fast Bits). It is designed as a complete drop-in replacement for the OEM diverter valve in late-model Mercedes vehicles.

Unlike the earlier generation diverter valves manufactured by Pierburg, the newer AMG-branded OEM valves cannot be disassembled and incorporated into a DV+. Therefore, GFB developed the T9388 with a low-profile integrated solenoid as a complete replacement for both the AMG and Pierburg diverter valves, enabling a hassle-free installation with no clearance issues.

Like all valves in the DV+ range, the new T9388 delivers the following benefits over the OEM diverter valve:

• Improved boost holding
• Sharper throttle response
• Faster boost recovery after a gearshift or brief throttle lift
• Unrivalled longevity, backed by our Lifetime Warranty

Improved Boost Holding

Since electronic OEM diverter valves first appeared in the mid-2000s, there have been many revisions over the years in an attempt to address reliability issues. Whilst the latest generation of OEM diverter valves has become more reliable, there is always a performance trade-off due to their operational method and plastic construction.

When GFB engineers performed boost leak testing on the OEM diverter valve in a C63S, they found the leak was significantly larger than in earlier generations.

This excessive leaking is due to the emerging trend of manufacturers mounting diverter valves remotely on plastic intercooler tanks rather than directly on the turbocharger. A plastic valve mechanism closing onto a plastic seat resulted in the largest OEM diverter valve leak we’ve seen yet at 28L/min at 1 Bar of boost.

Even with the Viton face seal (featured on all DV+ pistons), the plastic OEM seat face was found to be so uneven that it was impossible to achieve a reliable seal. The T9388 successfully addresses this issue by incorporating an integral piston seat machined into its body. This design ensures a proper seal, even on uneven plastic OEM seats.

Sharper throttle response, faster boost recovery after brief throttle lift

Factory electronic diverter valves are binary in operation – they’re either open or shut. Your throttle, however, isn’t. When you make small throttle adjustments, the binary operation of the factory diverter results in abrupt changes in power delivery, which is the very definition of poor throttle response.

The DV+ patented “pilot actuation” system allows the piston to open and close progressively, thereby smoothing the power delivery during throttle modulation, and ultimately improving throttle response.

Unrivalled longevity, backed by our Lifetime Warranty

The combination of precision manufacturing, attention to detail, and robust materials mean the DV+ will last a lifetime. So does the warranty!

Vehicle Applications:

MERCEDES-BENZ GLA-Class X156 GLA180/GLA200/GLA220/GLA250 (2014-2019)
MERCEDES-BENZ CLA-Class C117 CLA180/CLA200/CLA220/CLA250 (2013-2019)
MERCEDES-BENZ E-Class W212 E200/E250 (2009-2016)
MERCEDES-BENZ E-Class W212 E200/E250 (2009-2016)
MERCEDES-BENZ SLK 200/250 (R172)
MERCEDES-BENZ SLK 200/250 (R172)
MERCEDES-BENZ C-Class C180/C200/C250/C300 Turbo (Not Kompressor) 2011-2018
MERCEDES-BENZ C-Class C180/C200/C250/C300 Turbo (Not Kompressor) 2011-2018
MERCEDES-BENZ CLA-Class C117 CLA180/CLA200/CLA220/CLA250 (2013-2019)
MERCEDES-BENZ B-Class W246 B180/B200/B220/B250 (2011-2019)
MERCEDES-BENZ B-Class W246 B180/B200/B220/B250 (2011-2019)
MERCEDES-BENZ A-Class W176 A180/A200/A250 Turbo (2012-2018)
MERCEDES-BENZ A-Class W176 A180/A200/A250 Turbo (2012-2018)
MERCEDES-BENZ GLA-Class X156 GLA180/GLA200/GLA220/GLA250 (2014-2019)
MERCEDES-BENZ GLA-Class X156 GLA180/GLA200/GLA220/GLA250 (2014-2019)
MERCEDES-BENZ CLA-Class C118 CLA180/CLA200/CLA250e 1.3T (2019-On)
MERCEDES-BENZ A-Class W177 A160/A180/A200/A250e 1.3T (2018-On)
MERCEDES-BENZ GLB-Class X247 GLB180/GLB200 (2018-On)
MERCEDES-BENZ B- Class W247 B160/B180/B200/B250e (2018-On)
MERCEDES-BENZ A-Class W177 A160/A180/A200/A250e 1.3T (2018-On)
MERCEDES-BENZ GLC 200/250/300 (2015 - 2021)
MERCEDES-BENZ GLC 200/250/300 (2015 - 2021)
MERCEDES-BENZ C-Class C180/C200/C250/C300 Turbo (Not Kompressor) 2011-2018
MERCEDES-BENZ C-Class C180/C200/C250/C300 Turbo (Not Kompressor) 2011-2018
MERCEDES-BENZ E-Class W213 E200/E250/E300 (2016-2019)
MERCEDES-BENZ E-Class W213 E200/E250/E300 (2016-2019) Note : M270/M274 ENGINES ONLY
MERCEDES-BENZ S-Class S400 Note : Two Valves Required
MERCEDES-BENZ C-Class C180/C200/C250/C300 Turbo (Not Kompressor) 2011-2018
MERCEDES-BENZ C-Class C180/C200/C250/C300 Turbo (Not Kompressor) 2011-2018
MERCEDES-BENZ E-Class W212 E200/E250 (2009-2016)
MERCEDES-BENZ A-Class W176 A180/A200/A250 Turbo (2012-2018)
MERCEDES-BENZ A45 AMG (Facelift Models Only) (2015 - 2018)
MERCEDES-BENZ CLA45 AMG (Facelift Models Only) 2016 - 2018
MERCEDES-BENZ B-Class W246 B180/B200/B220/B250 (2011-2019)
MERCEDES-BENZ C63 & C63 S AMG 4.0TT (2016-On) Two Valves Required
MERCEDES-BENZ S63 AMG 4.0TT (2018-2020) Two Valves Required
MERCEDES-BENZ GLC63 & GLC63 S AMG 4.0TT (2018-On) Two Valves Required
MERCEDES-BENZ E63 & E63 S AMG 4.0TT (2018-On) Two Valves Required
MERCEDES-BENZ E63 & E63 S AMG 4.0TT (2018-On) Two Valves Required
MERCEDES-BENZ G63 AMG 4.0TT (2018-On) Two Valves Required
MERCEDES-BENZ C-Class C300 2.0T (2019-On)
MERCEDES-BENZ AMG GT 4.0TT (2019-On) Two Valves Required
MERCEDES-BENZ AMG GT 4.0TT (2019-On) Two Valves Required
MERCEDES-BENZ GLC43 AMG 3.0TT (2019-On) Two Valves Required
MERCEDES-BENZ CLA35 AMG 2.0T (2020-On)

• Sharper throttle response
• Faster boost recovery on gearshift
• Solves boost leaking issues
• Built to last

European manufacturers are pushing their engines to the limit. Get a DV to match.

GFB's DV+ diverter valve range offers a direct-fit performance solution for the weak factory diverter valves used on many modern vehicles. By retaining the factory ECU control and recirculating the vented air, the DV+ is a purely performance-orientated product.

GFB’s DV+ design solves the longevity and boost leaking issues that are common with factory diverter valves, and also changes the operation method to “pilot actuation” to ensure better performance on stock or modified engines.

Furthermore, these benefits won’t cost you the Earth! Rather than throwing the entire factory diverter valve system in the bin (like other manufacturer’s “solutions”), the DV+ keeps what works and replaces what doesn’t. It retains the factory solenoid and ECU control to ensure simple installation and reliable operation.

• 10% faster opening, 50% faster closing than the factory diverter
• Retains the factory solenoid for seamless integration
• Replaces plastic valve parts with metal for reliability and strength on stock or modified engines
• Direct-fit replacement with GFB’s TMS benefits
• Exclusive “pilot-actuated” valve mechanism for rapid response at high boost

Mercedes-Benz