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Hi all, I was hoping I could get some recommendations on who in Brisbane QLD can do ST upgrades ie installing a Turbo Smart BOV..
And has anyone done it themselves? Does it effect your Mountune tune?
 

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Hi all, I was hoping I could get some recommendations on who in Brisbane QLD can do ST upgrades ie installing a Turbo Smart BOV..
And has anyone done it themselves? Does it effect your Mountune tune?
I put a Kompact Shortie Plumb Back in my car and it's honestly not that hard to do. You will want to take the front right wheel off and get under the car to have access to the valve mounted on the turbocharger. You can do it without removing anything else, but if you want a bit more wiggle room you might like to take the belt cover off that's just next to the wheel and is secured with two torx screws and washers, as well as removing the charge pipe that comes out of the turbo with a 7mm socket.
I found snaking my right arm in from the wheel well while laying right underneath where the valve is gave me the best access and visibility.

If you can get the screws on and off the diverter valve first, and you have a torx that will fit the screw on the MAP sensor, then you should have everything you need to do the install.

This was pretty much my first time working on a car, so if you're in a similar position, make sure you're using jack stands any time you're going under your car and slide the wheel under the side for good measure. Safety glasses will also stop crud from falling into your eyes...

And no, the valve doesn't affect tuning. The way it works is when you get on the accelerator, boost pressure at the manifold flows into the vacuum hose on the valve and pushes on the back of the piston. That with spring pressure holds the valve closed, and it will stay closed as long as there's positive pressure at the manifold. When you release the go pedal, the throttle closes and a vacuum is formed in the manifold and in the back of the valve behind the valve's piston. The pressure differential pushes and sucks the valve open to let out the pressure in the hot side of the induction system.

I believe the car's stock diverter valve is solenoid operated, so it opens electrically rather than with pressure differential. There should be no tuning difference between the two valves, but at the same time there likely will be no performance gains either.

What DOES effect performance in terms of turbo-related valves is the wastegate. That is on the exhaust side of the turbo and it opens to redirect exhaust gasses away from the turbocharger's turbine to limit the RPM once the boost reaches a certain amount. In the Fiesta ST that amount is roughly 20psi depending on overboost and such stuff.

You really don't need to touch either of these systems unless they are malfunctioning or if you're after a different sound in the case of the diverter valve/BOV. I put the Kompact Shorting Plumb Back in for the sound. I machined some spacers from aluminium to compress the spring a bit in the valve which lets it still open, but it takes a bit more pressure, so at lower pressures there's a bit of flutter. Just my personal preference.

Something to note though, Turbosmart will happily sell you a 50/50 or Supersonic BOV which will vent to atmosphere, and I know for sure in Victoria these are ILLEGAL to have on the street, as they are very loud. Such may be the case in QLD too, so check your laws.

The plumb back models are more "different" sounding than loud, and as I said with the spacer, they can be adjusted to your taste by messing with the spring pressure. If you want to hear BOV noises legally, get a cold air intake instead, and look for ones with metal piping to better transmit the sound of your turbo. Just be very careful that what you get is designed for the European FiST, as the yanks have a different ECU that reads different sensors, and our cars will kick up a fuss if you install an intake designed for the American car. Mishimoto is a very good example. So buy stuff that you've seen working on a UK/AUS car under the conditions that you want it to work, and don't trust the stock that AU online stores have. They will sell anything to you, regardless of whether it works with out cars or not.
 
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