Boost Control Solenoids

Boost Control Solenoids: the valve that decides how hard your turbo works

A boost control solenoid sits in the vacuum/pressure line between your manifold and the wastegate actuator, and it bleeds or duty-cycles that pressure signal so the wastegate opens later than it would on the factory spring alone. That is what lets your ECU or standalone controller hold a target boost figure instead of letting the gate creep open early. Fit one when you want repeatable boost, quicker spool, or the ability to run more than one boost map. Most boost control solenoids here are 3-port or 4-port electronic units, and a few are full electronic controllers bundled with the solenoid.

What ThreePiece stocks

There are 33 boost control solenoids and controller kits in stock, priced from $63 to $695 at current in-stock levels - that is a snapshot, not a locked price. The range spans 12 brands, including Turbosmart, COBB, Go Fast Bits, BorgWarner, Perrin Performance, Turbo XS, Haltech, Snow Performance, AEM, Mishimoto, Torque Solution and Vibrant.

At the top sits the Turbosmart BlackBox Electronic Wastegate Controller and the Turbosmart BOV controller kit with custom Raceport. Mid-range, the GFB G-Force III Electronic Boost Controller with 4-port solenoid pairs a controller and valve in one box. For direct-fit vehicle-specific units, look at the COBB 3-port solenoid for the 15-21 Subaru WRX and the COBB 3-port solenoid for 04-07 STI / 02-07 WRX / 04-08 FXT. Turbo builders can grab the BorgWarner BCSV kit for EFR turbos.

Of the range, 19 products list fitment data, covering model years 2002 to 2024. Top makes are Subaru, Audi, Mitsubishi, Mazda and Volkswagen - think Subaru WRX and STI, Forester XT, Mitsubishi Evo X and Ralliart, Audi and Volkswagen 2.0T, and Mazda MS3/MS6.

How to choose

  • Vehicle-specific vs universal: a COBB direct-fit solenoid plugs into the factory harness and is controlled by your existing tune, so there is no separate box to mount or wire. A universal solenoid gives you freedom on any turbo setup but needs plumbing and a controller to drive it.
  • Solenoid only vs controller kit: if your ECU or standalone already has a boost control output, you only need the valve. If it does not, a GFB or Turbosmart controller-plus-solenoid package handles the duty cycle for you.
  • 3-port vs 4-port: 4-port solenoids can bleed both sides of the actuator for finer control, which matters more on aggressive builds; a 3-port covers most street and bolt-on setups.

What else you need with it

Plumbing a solenoid means vacuum line and connectors - check Fittings and Adapters. If you are turning up boost you will lean on fueling, so browse Fuel Pumps, keep charge temps in check with Radiators, and if the build is coming apart, review Head Gaskets. See everything under the Engine Components section.

Fitment and ordering

Not sure a solenoid matches your setup? Call fitment help at 813-535-5801 or reach us through contact us. Every order ships free, and Affirm and Katapult financing is available at checkout.

Boost Control Solenoids: the valve that decides how hard your turbo works

A boost control solenoid sits in the vacuum/pressure line between your manifold and the wastegate actuator, and it bleeds or duty-cycles that pressure signal so the wastegate opens later than it would on the factory spring alone. That is what lets your ECU or standalone controller hold a target boost figure instead of letting the gate creep open early. Fit one when you want repeatable boost, quicker spool, or the ability to run more than one boost map. Most boost control solenoids here are 3-port or 4-port electronic units, and a few are full electronic controllers bundled with the solenoid.

What ThreePiece stocks

There are 33 boost control solenoids and controller kits in stock, priced from $63 to $695 at current in-stock levels - that is a snapshot, not a locked price. The range spans 12 brands, including Turbosmart, COBB, Go Fast Bits, BorgWarner, Perrin Performance, Turbo XS, Haltech, Snow Performance, AEM, Mishimoto, Torque Solution and Vibrant.

At the top sits the Turbosmart BlackBox Electronic Wastegate Controller and the Turbosmart BOV controller kit with custom Raceport. Mid-range, the GFB G-Force III Electronic Boost Controller with 4-port solenoid pairs a controller and valve in one box. For direct-fit vehicle-specific units, look at the COBB 3-port solenoid for the 15-21 Subaru WRX and the COBB 3-port solenoid for 04-07 STI / 02-07 WRX / 04-08 FXT. Turbo builders can grab the BorgWarner BCSV kit for EFR turbos.

Of the range, 19 products list fitment data, covering model years 2002 to 2024. Top makes are Subaru, Audi, Mitsubishi, Mazda and Volkswagen - think Subaru WRX and STI, Forester XT, Mitsubishi Evo X and Ralliart, Audi and Volkswagen 2.0T, and Mazda MS3/MS6.

How to choose

  • Vehicle-specific vs universal: a COBB direct-fit solenoid plugs into the factory harness and is controlled by your existing tune, so there is no separate box to mount or wire. A universal solenoid gives you freedom on any turbo setup but needs plumbing and a controller to drive it.
  • Solenoid only vs controller kit: if your ECU or standalone already has a boost control output, you only need the valve. If it does not, a GFB or Turbosmart controller-plus-solenoid package handles the duty cycle for you.
  • 3-port vs 4-port: 4-port solenoids can bleed both sides of the actuator for finer control, which matters more on aggressive builds; a 3-port covers most street and bolt-on setups.

What else you need with it

Plumbing a solenoid means vacuum line and connectors - check Fittings and Adapters. If you are turning up boost you will lean on fueling, so browse Fuel Pumps, keep charge temps in check with Radiators, and if the build is coming apart, review Head Gaskets. See everything under the Engine Components section.

Fitment and ordering

Not sure a solenoid matches your setup? Call fitment help at 813-535-5801 or reach us through contact us. Every order ships free, and Affirm and Katapult financing is available at checkout.