If you’re looking to upgrade your ride’s clutch setup, the ACT MS1-HDG4 Heavy Duty/Race Sprung 4 Pad Kit is where it’s at. This isn’t just any clutch kit; it’s built for those who want a serious performance boost without sacrificing reliability. I've installed this kit on my own Mitsubishi Starion, and let me tell you, it’s a game changer.

The heart of this kit is ACT's Heavy Duty pressure plate, which is designed with an exclusive diaphragm that cranks up the clamp load while keeping deflection to a minimum. What does that mean for you? More grip and longer clutch life, plain and simple. Each diaphragm goes through a meticulous four-stage heat-treating process, so you know it’s tough enough to handle whatever you throw at it.

Now, let’s talk about the 4-pad spring-centered race disc. This bad boy is all about performance. It features a spring-center that dampens torsional vibrations, making for a quieter ride even when you’re pushing your engine hard. Sure, the engagement can be a bit aggressive, but that just means faster shifts when you need them most. It’s perfect for smaller engines where every bit of performance counts.

One of the coolest things about this kit is the way the spring retainers are designed. With wraparound spring windows and thicker stampings, you get extra support and reduced stress, which translates to better durability. It’s all about reliability, especially during those high RPM runs.

In terms of specs, you’re looking at a clutch disc diameter of 9.4 inches (240 mm), and it’s made from high-tolerance ceramic material that can handle the heat. The torque capacity is impressive at 420 ft/lbs, which is a solid step up over stock. Just remember, this kit doesn’t come with a clutch master cylinder or pressure plate bolts, but it does include grease and a pilot bearing, so you’re not left hanging.

Whether you’re hitting the streets or the track, this kit is recommended for high horsepower applications. It’s been 100% clamp load tested and dynamically balanced, ensuring smooth operation even at high RPMs. If you’re serious about your performance, this is definitely worth considering.

Install Instructions:

• For Instructions CLICK HERE

Features:

• Light to moderate pedal effort with aggressive engagement
• Moderate friction life, extended by ACT's exclusive diaphragm design
• Engineered for high heat tolerance and performance with select ceramic materials
• Perfect for high horsepower street or race use
• 100% clamp load tested and dynamically balanced for reliability

Specifications:

• Clutch Master Cylinder Included: No
• Grease Included: Yes
• Grade Type: Performance
• Pilot Bushing Included: No
• Pressure Plate Type: Heavy Duty
• Release Bearing Included: Yes
• Clutch Disc Diameter: 9.4 in
• Clutch Disc Diameter: 240 mm
• Disc Material: Ceramic
• Input Spline Quantity: 23
• Input Shaft Diameter: 1 in
• Alignment Tool Included: Yes
• Disc Type Sprung Solid: Sprung
• Pressure Plate Bolts Included: No
• Clutch Slave Cylinder Included: No
• Flywheel Bolts Included: No
• Pilot Bearing Included: Yes
• Product Weight (lbs.): 15.7
• Torque Capacity (ft/lbs.): 420
• Torque Capacity Over OE: 0.72

Products Fitment:
Chrysler Conquest 1987-1989
Mitsubishi Starion 1987-1989