TS-0604-1067 - vIWG N20 BMW - Instructions

TS-0604-1067 - vIWG N20 BMW - Instructions

Product Name:

vIWG N20 BMW – 6inHG

Product Description:

vIWG N20 BMW – 6inHG

Product Number:

Important Notes on Your Vacuum Internal Wastegate

  1. Turbosmart accepts no responsibility for the incorrect installation of this product which is potentially hazardous and can cause serious engine damage or personal injury.
  2. The Vacuum Internal Wastegate (VIWG) is designed as a factory replacement for Vacuum-operated turbocharger applications.
  3. Ensure the engine is cold before installation.


  1. Turbosmart recommends that an appropriately qualified technician fits your VIWG
  2. The vacuum IWG requires the wastegate to be set at a certain Vacuum pressure to operate correctly. Vacuum Pumps are only sometimes a part of a basic tool set.

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Kit Contents

Please check that the following items have been provided in your Vacuum Internal Wastegate packaging.





Turbosmart Vacuum Wastegate

Main unit


Turbosmart Sticker


Instruction Card


2 x M6 Nuts and Washers 

Nuts required for installation


1/16 NPT Nipple and Blank

Nipples and Blanks are required for the bottom port.


¼ UNF Nut

Clevis Locking Nut


N20 Clevis 


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Figure 1 - Kit Contents

Tools Required

  1. Basic Socket Set
  2. Vacuum Operated Hand Pump

About Your Vacuum Internal Wastegate 

​Turbosmart Upgraded Vacuum-operated Wastegate Actuators have been developed to provide the maximum possible boost response for your factory frame turbocharger. The Turbosmart vIWG Series of upgraded Actuators benefit from an increased 'Working Ratio' over the factory equipment resulting in improved boost response throughout the RPM range.

This Improved 'working ratio' is achieved through an increase to the effective surface area of the diaphragm & revisions to the actual springs fitted, resulting in greater leverage of the forces the actuator is working against (boost and backpressure) while still being super-responsive. 

Upgrading with the same base pressure as the factory, you can expect a broader boost & torque curve through peak boost being achieved earlier in the RPM and being held longer into higher RPM. These improvements can be amplified with higher base pressures; however, tuning & recalibration are recommended for optimal performance.

Fitting Your Vacuum Internal Wastegate

  1. Identify OEM Wastegate Actuator Location

On the model designation 6th Generation BMW 3 Series (F30/1/4/5) N20 Engine, the Wastegate Actuator valve is located on the underside of the turbo side. This engine is common in the BMW fleet, and some applications might be slightly different. 

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It may be required to remove auxiliary components to access the Wastegate Actuator. Ensure you consult your local specialist or a service manual for correct disassembly procedures.

Ensure the engine has cooled down to ambient temperature before proceeding. 

  1. Removing OEM Vacuum Actuator

The actuator is held onto the car with 3x 10mm bolts on the back of the vacuum canister. These are easily removed and placed back onto the vacuum canister once removed from the car. We also need to undo the clevis arm bolt, an 11mm nut. We need this undone slightly to allow us some compliance in removing it from the car. There are two T30 bolts. This is possibly the easiest way to remove the canister from the car.

  1. Removing OEM Vacuum Actuator Clevis

Once the actuator is undone, we need to remove the R Clip that holds the arm onto the actuator arm. The best way to remove this is to hold the clip with angled pliers. These clips generally want to shoot off and get lost under the car. So, the best suggestion is to push it down and hold the clip as it is removed.

  1. Fitting your Turbosmart Vacuum Actuator

With installation, we would like to match the rod length to the original actuator as closely as possible. Once set, we need to place it into the car. The actuator bolts will need to be set and tightened down. It is very easy to drop the bolts, so ensure the passage from underneath is ready to catch and help install the bolts. We will leave the last rod bolt loose on the clevis.

  1. Setting your Turbosmart Vacuum Actuator

The VIWG requires the actuator to be set at a certain Vacuum pressure. This is defined by the spring, with the Mini we need to set at 6inHg (203mmbar) of vacuum to fully seat the wastegate flap. Once the pressure is achieved, we need to move the nut up to the clevis. Unnecessary preload will limit rod stroke and hamper performance. It needs to be just enough to seat correctly. The bottom port must Vent to atmpsohere in this case. 

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  1. Vacuum Plumbing

With the Valve in place we can connect the actuator to the OEM Vacuum Signal. The hose is attached to a barb fitting to ensure a good seal. 

NOTE: The bottom port must be left to vent to atmosphere when used solely as a Vacuum actuator.

  1. OPTIONAL Positive Pressure Assistance Plumbing

The VIWG can be used with Postive Pressure assistance. This is located by the black circle. We can use positive pressure that is controlled by the ECU to assist the vacuum system(Top Port) from not being overcome. 

The grub screw must be used in this application to allow for pressure to be maintained in the bottom port. 

  1. Fitting removed parts required for vIWG install

With the vIWG being fitted to the car and connected. The parts that have been removed must now be stored safely.

Congratulations, your Turbosmart VIWG is installed and ready for use. Double check all connections and mounting screws. Start your engine and check for leaks. 


  1. Any issues must be resolved before heavy driving.
  1. The car feels sluggish, rod length and pressure required to seat flap are incorrectly set. Ensure correct pressure is achieved to seat fully. 
  1. Car over boosts, the same as above, the rod is set at a pressure too low, allowing for it to close before being commanded.
  1. Failing the above, submit a Technical Support Query Form with information about your engine, oil type and photos of the installation and one our expert technicians will respond as soon as possible.