Bailey Motorsport Diverter Valve for Audi B5 S4
Wondering where your boost went? Power delivery not as smooth as it used to be? Most likely your engine's diverter valves are to blame.
Features
What is a diverter valve? A diverter valve (DV) is a pathway for boost when it is not being used by your engine. Whenever the throttle body is closed, like during shifts or decelleration, the boost needs an escape route. If the boost cannot escape during these times, it can back up and cause shocks to the turbos. These shocks will stall the turbos, slowing boost production upon re-acceleration (turbo lag). Even worse, these shocks can cause damage to the turbos. The diverter valves’ job is to open when the throttle body is closing or closed, and reroute the boost to the low pressure intake side of the turbos, where it can do no harm.
Bailey Motorsport has developed a direct-replacement, alloy body diverter valve that eliminates all of the above problems.
The Bailey Motorsport DV30 diverter valve uses a high temperature composite piston instead of a rubber diaphragm, which reacts much faster and more predictably. These piston-type valves can handle up to 4 bar (~60 psi) of boost and have ~75% more flow capacity than the stock valve. By reacting faster, turbo compressor stalling and the resulting turbo lag are greatly reduced.
Each and every valve is pressure-tested prior to leaving the manufacturing process. Highly recommended for all turbo engines utilizing the Bosch DV, they are a very easy 30 minute bolt-in with the included detailed instructions.
Bailey Motorsport is famous for their strict quality control when manufacturing their products, which means that you, the user, is ensured of proper performance.
These valves really do make a tangible difference in the way the boost builds during throttle application.
A 996 Twin Turbo owner on Funcarsonline recently posted:”I really regret installing the Baileys….so late. The performance degradation with the stock diverter valves occured over such a long period of time that I didn’t notice the difference. Wow. 8-9 mph faster at the end of the front straight today with the Baileys. Much better acceleration. I had to change all of my braking points. Even if your car isn’t ‘honking,’ you should consider replacing the stock DVs.”
There are dozens of diverter valves now available for the turbo charged Porsches and Audis, yet none of them have the versatility, history, and reliability of the Bailey Motorsport diverter valves. Fix your problems once and for all with the Bailey Motorsport diverter valves. Please Note B5′s and 996 twins require two of these valves per application.






