Wastegate Plumbing

External Wastegate

Connections:

  1. Source boost pressure from the turbo outlet or the hot side intercooler pipe.
  2. Connect the pressure source to a T-piece fitting.
  3. Connect the one of the other two T-piece connections to the wastegate's bottom pressure port.
  4. Connect the remaining T-piece connection to the solenoid's Normally Closed port. This is the port that you cannot blow through when the solenoid is off.
  5. Connect the Common port on the solenoid to the wastegate's top pressure port.
  6. Leave the Normally Open port open to atmosphere. Alternatively, this can be plumbed into the turbo's intake pipe.
  7. Ensure that any spare or alternate port fittings in the top and bottom housings are blanked off.

 

Operation:

  • When the solenoid is off, boost pressure passes straight through the T-piece to the wastegate's bottom port. The Normally Closed solenoid port blocks the escape of pressure on this run. The wastegate opens when the boost pressure exceeds the spring pressure.
  • When the solenoid is energised, boost pressure sourced from the turbo via the T-piece is allowed to pass through the solenoid to the wastegate's top port. This raises the effective wastegate spring pressure, which causes the boost to rise.
  • When the solenoid is pulsed by the ECU or the Boost Controller, the effective spring pressure created by adding boost into the spring housing is varied to achieve the desired rise in boost pressure.

Internal Wastegate (Single Port)

Connections:

  1. Source boost pressure from the turbo outlet or the hot side intercooler pipe.
  2. Connect the pressure source to the Normally Open port in the control solenoid. This is usually the front/centre port.
  3. Connect the Common port on the solenoid to the wastegate pressure port.
  4. Leave the Normally Closed port open to atmosphere. Alternatively, this can be plumbed into the turbo's intake pipe.

 

Operation:

  • When the solenoid is off, boost pressure passes straight through the solenoids Normally Open into the wastegate, causing it to open as the boost pressure exceeds the wastegate spring pressure.
  • When the solenoid is energised, boost pressure sourced from the turbo is blocked and the pressure inside the wastegate is vented out of the solenoids Normally Closed port, which is now open. This causes the wastegate to close and the boost pressure to rise.
  • When the solenoid is pulsed by the ECU or the Boost Controller, the effective pressure acting on the wastegate spring is varied to achieve the desired rise in boost pressure.

Internal Wastegate (Dual Port)

Connections:

  1. Source boost pressure from the turbo outlet or the hot side intercooler pipe.
  2. Connect the pressure source to a T-piece fitting.
  3. Connect the one of the other two T-piece connections to the wastegate's top pressure port.
  4. Connect the remaining T-piece connection to the solenoid's Normally Closed port. This is the port that you cannot blow through when the solenoid is off.
  5. Connect the Common port on the solenoid to the wastegate's bottom pressure port.
  6. Leave the Normally Open port open to atmosphere. Alternatively, this can be plumbed into the turbo's intake pipe.

 

Operation:

  • When the solenoid is off, boost pressure passes straight through the T-piece to the wastegate's top port. The Normally Closed solenoid port blocks the escape of pressure on this run. The wastegate opens when the boost pressure exceeds the spring pressure.
  • When the solenoid is energised, boost pressure sourced from the turbo via the T-piece is allowed to pass through the solenoid to the wastegate's bottom port. This raises the effective wastegate spring pressure, which causes the boost to rise.
  • When the solenoid is pulsed by the ECU or the Boost Controller, the effective spring pressure created by adding boost into the spring housing is varied to achieve the desired rise in boost pressure.