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SteamSpeed 4-Port Boost Control Solenoid (BCS) Universal

Regular price
$145.00 USD
Regular price
$300.00 USD
Sale price
$145.00 USD

The SteamSpeed 4-port Electronic Boost Controller ups the ante again.  Our 3-port controller is vastly superior to the stock units, but our 4-port version goes further providing the maximum level of boost control available allowing more sophisticated boost control schemes allowing the tuner to have even more control and wider ranges of operation of the wastegate.

Our 4-port controller can be used in many configurations, so consult your tuner to understand if a 4-port controller is right for your build, but typically, 4-port controllers are used with an aftermarket wastegate with ports on both sides of the wastegate's diaphragm.  The 4-port controller allow fine control on both sides of the diaphragm which provides finer grain control of the spring preload, etc. which enables a broader range of boost control on the wastegate.  Cool right?

If your goal is to use the controller on both sides of the diaphragm, then you need to have a wastegate that supports it.  Many of our wastegates do have ports on both sides of the diaphragm, so they may be used in this way, but typically, this type of controller would be used with the larger external wastegates, like the ones used in a STI's rotated turbo setup.  If your turbo's wastegate is only one port, then you'd probably use one of our 3-port controllers.

Kit components:

  • At the center, is our custom 4-port pneumatic MAC valve designed for heavy industrial applications, high performance, and durability.  However, our valve is a custom unit we designed with MAC with a few essential modifications, like waterproofing, which make them even better for being used boost control.  Other companies that offer 4-port valves, just use MAC catalog spec'ed units that don't have waterproofing, for example, and simply replace the sticker.
  • Waterproof connectors.  The male connector is the same style and fitment of the Sumitomo connectors used on WRX/STIs and Evos for their stock boost controllers, so if you have one of these cars, the connector is plug-and-play with the stock engine harness.  If your car doesn't have that Sumitomo connector on the harness, or you are simply doing something more custom, we also provide the female connect to wire into your project.
  • The Pneumadyne 1/4" NTP barbs fittings we provide are the highest quality, sized for 6mm ID hoses commonly used on Japanese cars for boost controllers.