Kinugawa Turbo Big Head Adjustable Internal Wastegate Actuator — Single & Dual Port, 2-in-1 Integrated Spring

Kinugawa Big Head Adjustable Internal Wastegate Actuator — Single & Dual Port, 2-in-1 Integrated Spring The Kinugawa Big Head Adjustable Wastegate Actuator is a direct-fit, bolt-on upgrade engineered to solve one of the most common boost control failures in turbocharged engines: premature wastegate opening under high boost. The factory actuator's weak diaphragm spring allows the wastegate to blow open before target boost is reached, robbing mid-range torque and limiting peak power. Kinugawa's enlarged diaphragm head and precision-wound integrated spring hold the wastegate closed longer — delivering quicker spool, sharper throttle response, and sustained peak boost. Available in boost pressure ratings from 3 PSI to 26 PSI, this actuator features a 2-in-1 integrated spring design that makes it compatible with both single-port and dual-port wastegate configurations without modification. Why Upgrade to the Kinugawa Big Head Actuator? Enlarged diaphragm area increases spring pressure and wastegate hold force Keeps the wastegate valve seated longer for higher peak boost achieved sooner Produces strong torque from idle through the entire RPM range Crisp, controlled boost response — eliminates boost creep and mid-range sag 2-in-1 integrated spring: single and dual port exchangeable in one unit Adjustable rod length with 2mm preload for precise installation fit Single Port vs. Dual Port — What's the Difference? Single Port Actuators Boost reference is supplied to one side of the diaphragm. The wastegate opens in one direction; spring pressure alone handles the return stroke and holds the wastegate closed. Best suited for basic boost control via a manual boost controller (MBC) or electronic boost controller (EBC). Simple plumbing, straightforward setup — ideal for street and mild performance builds. Dual Port Actuators Boost reference is supplied to both sides of the diaphragm, enabling bidirectional control of the wastegate — both opening and closing. Spring pressure is pneumatically assisted on the return stroke, allowing a softer spring to achieve the same or higher boost targets with greater precision. Recommended for high-boost applications, high exhaust backpressure environments, or oversized wastegates. Best used with an EBC for maximum tunability. Tech Tip: Dual port actuators can also be run as a traditional single port — simply leave the lower actuator port vented to atmosphere. This makes the Kinugawa 2-in-1 design a future-proof choice for any build. Integrated Spring Pressure Reference Spring configurations: 3 PSI inner / 7 PSI inner / 7 PSI middle / 11 PSI middle / 10 PSI outer / 7 PSI outer. Select your target boost pressure from the variant selector above. Installation Notes Designed for internal wastegate turbochargers Apply 2mm of preload to the actuator rod during installation For clevis-type applications: set 2mm preload on the wastegate valve arm, then verify with compressed air at a pressure slightly above the actuator's rated spring pressure Spring surface paint is used for color identification only — it does not affect spring function or performance Kit Contents 1 × Kinugawa Big Head Dual-Port Adjustable Wastegate Actuator Head 1 × Installation Instruction Sheet (download PDF) Product Details Brand: Kinugawa Turbo Systems Condition: Brand New Port Type: Single & Dual Port (2-in-1 Integrated) Boost Pressure Range: 3 PSI – 26 PSI (select variant) Country of Origin: Taiwan HS Code: 841191 Weight: 1 kg