Description
The ACT Mod-Twin 225 Heavy Duty Sprung Street Clutch Kit is engineered for high-powered street and street/strip applications where increased torque capacity, smooth engagement, durability, and dependable performance are essential. Designed around ACT's modular twin-disc clutch technology, this kit combines two organic friction surfaces with an ultra-durable sprung Mono-Drive hub assembly to deliver up to 690 ft/lbs of torque capacity, approximately 44% more than the OE clutch.
The ACT Mod-Twin 225 uses premium organic friction material on steel-backed friction plates to provide a stable coefficient of friction, strong heat capacity, smooth engagement, and extended clutch life. Its sprung Mono-Drive hub helps absorb torsional vibration, reduce driveline shock, and minimize stress on the transmission input shaft. The system is designed to provide a soft, progressive pedal feel while maintaining the holding power needed for modified and high-output vehicles.
Each diaphragm spring undergoes ACT's exclusive four-stage heat-treating process to provide consistent clamping performance and light pedal effort. The forged aluminum cover, hardened wear points, premium friction materials, and precision-engineered components are designed to withstand demanding street and performance driving conditions.
The complete Mod-Twin assembly includes a CNC-machined and dynamically balanced flywheel, pressure plate cover, diaphragm spring, friction plates, sprung Mono-Drive hub assembly, floater, patented Monoloc Collar, release bearing, alignment tool, and pilot bearing where required. The ACT Mod-Twin system is fully rebuildable, with most components available separately for long-term serviceability.
Fitment
BMW 3.0L Turbo B58 Applications
- 2016–2018 BMW 340i
- 2016–2018 BMW 340i xDrive
- 2017–2019 BMW 440i
- 2017–2018 BMW 440i xDrive
- 2017–2021 BMW M240i
Toyota GR Supra 3.0L Applications
- 2023 Toyota GR Supra A91-MT Edition
- 2023–2026 Toyota GR Supra Base
- 2023–2026 Toyota GR Supra Premium
- 2023 Toyota GR Supra Special Edition
- 2024 Toyota GR Supra 45th Anniversary Edition
- 2024 Toyota GR Supra Premium 45th Anniversary Edition
- 2024 Toyota GR Supra Special Edition
- 2026 Toyota GR Supra A90 Final Edition
- 2026 Toyota GR Supra MkV Final Edition
Engine: 3.0L inline 6-cylinder gasoline, 2998cc, DOHC
Key Features
- ACT Mod-Twin 225 Heavy Duty Sprung Street Clutch Kit
- Part Number: T1SS-B02
- 690 ft/lbs torque capacity
- 44% greater torque capacity than OE
- Twin organic friction surfaces
- 225 mm clutch disc diameter
- Sprung Mono-Drive hub assembly
- Heavy Duty pressure plate
- Soft, progressive engagement
- Light and consistent pedal feel
- Smooth shifting characteristics
- High heat capacity and durability
- CNC-machined and dynamically balanced flywheel
- Forged aluminum pressure plate cover
- Patented Monoloc Collar
- Fully rebuildable modular design
- Designed for Street and Street/Strip use
- Computer spin-balanced to within 0.25 oz-in
- Includes alignment tool and pilot bearing where required
Specifications
| Specification | Details |
|---|---|
| Brand | ACT |
| Part Number | T1SS-B02 |
| Product Description | Mod-Twin 225 Heavy Duty Sprung Street Clutch Kit |
| Product Weight | 33.1 lbs |
| Torque Capacity | 690 ft/lbs |
| Torque Capacity Over OE | 44% |
| Disc Material | Organic |
| Clutch Disc Diameter | 8.8 inches / 225 mm |
| Input Shaft Diameter | 1.375 inches |
| Pressure Plate Type | Heavy Duty |
| Recommended Use | Street / Street-Strip |
Performance and Durability
Feel: The ACT Mod-Twin delivers soft, progressive engagement, light pedal effort, and smooth shifting with mild to moderate transmission gear noise.
Life: The forged aluminum cover, Mono-Drive hub, specially treated diaphragm spring, premium friction materials, and hardened wear points are designed for long-term durability under demanding conditions.
Quality: ACT combines robust construction, carefully selected materials, strategic engineering, and precise manufacturing tolerances to provide high performance and heat tolerance.
ACT Difference: ACT applies tactical engineering to its Mod-Twin platform to address common compromises associated with twin-disc clutches. The result is a durable, serviceable, long-lasting clutch with high torque capacity. ACT clutch assemblies are clamp-load tested, dynamically balanced, and SFI certified.
Break-In Recommendations
For the organic street friction discs, ACT recommends a 300–500 mile break-in period using mild engagement and normal stop-and-go driving before racing or aggressive driving. Avoid overheating the clutch during break-in, as excessive heat can cause friction surfaces to fuse, develop hot spots, or glaze.
Frequently Asked Questions
Are ACT clutches balanced?
Yes. ACT clutch assemblies are computer spin-balanced to within 0.25 oz-in for smooth operation throughout the RPM range. For comparison, stock production clutches are typically balanced to within 0.50 oz-in.
Will an ACT clutch increase pedal effort?
ACT Heavy Duty pressure plates are designed for high-torque applications. Depending on the application, Heavy Duty pressure plates can increase pedal effort by approximately 15–40%. This increased clamping force helps provide the torque capacity and durability required for performance applications.
Do ACT clutches require a break-in period?
Yes. ACT recommends breaking in organic street discs for approximately 300–500 miles with mild engagement before racing or spirited driving. Avoid excessive heat during this period.
Are ACT clutches repairable or rebuildable?
The ACT Mod-Twin is designed as a modular, rebuildable clutch system. Depending on the condition of the assembly, repairs or rebuilds may be possible following inspection. ACT recommends that servicing be performed by qualified technicians familiar with the Mod-Twin system.
How much does the ACT clutch weigh?
The ACT clutch assembly weighs approximately 33.1 lbs and is generally comparable to the weight of a stock OEM clutch assembly.
