Fitting a Dump valve.
To install a dump valve, a hole must be drilled in the side of the plenum chamber, as shown here. A small pipe can then be either welded in place, or threaded and tapped in place, as i did. A piece of hose is then used to connect the dump valve to the plenum, jubilee clips hold the connections securely. The other end of the dump valve is then connected to the inlet manifold via a length of hose. The manifold must have a small connection tapped in, if one is not already available.
Do remember to remove and block the hole in the plenum where the standard spring/plunger valve is fitted.
So there you go, its as simple as that. Now get to it !!

Here you can see the connection into the manifold.

I now use a Kevlar reinforced dump valve diaphragm, as i have split several standard items. The one pictured left was supposed to be "uprated", but only lasted 1hour at 10psi of boost. The Kevlar one has lasted years so far at up to 20psi.
Though after a while the rubber seems to become perished with age and cracks. It is well worth while checking it on a regular basis, or keep a spare handy.

Installing a bleed valve.
The Metro Turbo as standard is fitted with an ECU. This is used to control the boost. Basically it acts like an electronic bleed valve. Below 4,500rpm the boost is limited to 4psi, above this the ECU raises the boost level to 7psi. The reason for the fitment of this was to limit the huge midrange torque the Turbo provides. This helped increase the life of the transmission.
Most people who fit the Metro Turbo engine in Mini abandon the ECU. When this is done the boost is now limited to a constant 4psi. To raise the boost above this a bleed valve can be used. On a standard engine with standard compression etc it will be best to stick to 7psi max. Only when your engine is built to run more boost is it advisable to turn up the bleed valve.
If you set the bleed valve to 7psi you will now see that throughout the rev range, once on boost.

Assuming the ECU is removed. Block up the float chamber venting valve on the carb. Remove the boost solenoid etc.
The bleed valve is now connected in line between the actuator and the Turbo. It can either be left under the bonnet or positioned in the car, as i have done.
Make sure you have an acurate boost gauge. Drive the car and turn the bleed valve small amounts until the required setting is reached.
Remember a small turn will increases the boost quite a lot so be careful. Try the car in all gears and throughout the rev range, until youre happy with the setting.
Remember dont go silly, be sensible with the boost and only run what your engine can handle.