Plenum Sprung Valve
Turbo Mini Forums

do i need to plug this if running around 10psi? It'll blow off too early otherwise surely?

yeah. I actually got the hole where mine goes welded over and machined flat. Nice and smart!

Hannibal: There are two ways we can do this: the easy way and the hard way. In a few minutes my friends and I are going to come down on you like your worst nightmare. You're gonna wish the Earth had opened up and swallowed you whole.
bad guy: What's the easy way?
Hannibal: That WAS the easy way.

Or retain it with a stronger spring so that it will stay seated at whatever boost level you choose?

I am keeping it functioning on my car as a "just in case" type of thing, only takes a split hose to the actuator and you then have no boost control........OK if you are watching the gauge but otherwise will cause the engine to very very quickly run lean.

or fill with several 5ps to make the spring stronger

the montego turbo plenum spring available from rover dealers while they are still in business is about 80p and copes with 10 psi , can be bought for lots more money from turbo specialists