Fit a Dump Valve
What is a Dump Valve (DV)?
Read the What is a Dump Valve article
Whereabouts does this fit?
A DV is fitted after the turbo and before the throttle body. On the 165 this fits nicely between the turbo outlet and the intercooler inlet. On the 185 this can be fitted between the intercooler and turbo with the fitting kit, but there is very little room.
The 205 comes as standard with a recirculating type DV. There are various replacement kits available to bolt the DV onto the side of the airbox or onto the side of an induction kit/pipe. Alternatively the stock DV mounting can be blocked off and a DV attached directly to the front of the intercooler.
Ideally a DV should be fitted as close to the throttle body as possible.
What about this "other" pipe that comes off the DV?
The other vacuum pipe attaches to the cylinder side of the throttle body. Simply connect to the unused connection on the left hand side of the manifold or use a T-piece and connect into an existing pipe. Do not connect into the FPR vacuum line. Have a look at the Boost Gauge article as you may want to do this at the same time.
|DV installed between turbo outlet and intercooler inlet. Note the use of the red Samco 'T-piece'. This arrangement can be used on the 165 and the 185||'Other pipe' connected to the left hand side of the manifold. 165 manifold shown||Another view of the available connections to attach the DV. 165 manifold shown|
What should I fit?
I would recommend fitting the Bailey DV26 with 5psi spring. You can buy this as a kit from Bailey Motorsport. The kit includes the DV and a Samco 'T-piece' so that you can install the DV. Price DV ~£90, fitting kit ~£40. I found the people at Bailey's helpful and knowledgeable...
Other recommended DVs are the HKS super Sequential and the Blitz SuperSound - I like the Blitz, top bit of kit!
All dump valves are pretty much the same. In my opinion do not get the diaphragm variant as these split. Get the Samco hose 'T-piece' to attach the DV, as shown in the left hand picture above for the 165 and 185. Bailey Motorsport can supply you with one of these in various colours. The DV26 and fitting kit is available through most dealers as a standard Samco hose T-piece.
For the 205 I would fit a DV mounted to the front of the intercooler on a 30mm piece of Samco hose