Description
The ACT Mod-Twin 225 Heavy Duty Rigid Race Clutch Kit is engineered for high-powered BMW B58 and Toyota GR Supra applications where aggressive launches, rapid shifting, extreme torque capacity, and race-level durability are essential. With a massive 1,060 ft/lbs of torque capacity, this ACT twin-disc clutch delivers 122% more torque capacity than the OE clutch, making it a serious upgrade for high-output drag, road, and rally racing vehicles.
The T1R-B02 Mod-Twin 225 HD Rigid Race Kit combines two ceramic friction surfaces with a solid Mono-Drive hub in a lightweight, fully modular design. The rigid chrome-moly Mono-Drive hub is heat-treated for strength and durability and features a continuous spline that helps extend transmission input shaft life. Its lightweight rigid construction is designed to support quicker shifts and dependable performance under severe racing conditions.
Puck-style friction plates use high-quality ceramic friction material to provide a high coefficient of friction, superior heat capacity, and long clutch life. Each diaphragm spring undergoes ACT's exclusive four-stage heat-treating process to provide consistent performance and light pedal effort.
The complete ACT Mod-Twin 225 HD Rigid Race clutch includes a CNC-machined and dynamically balanced flywheel, pressure plate cover, diaphragm spring, ceramic friction plates, rigid Mono-Drive hub, floater, patented Monoloc Collar, release bearing, alignment tool, and pilot bearing when required. The 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
- 2017–2018 BMW 440i
- 2017–2018 BMW 440i xDrive
- 2017–2021 BMW M240i
- 2019 BMW 440i
- 2019 BMW 440i xDrive
- 2019 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 L6 gasoline, 2998cc, DOHC
Key Features
- ACT Mod-Twin 225 Heavy Duty Rigid Race Clutch Kit
- Part Number: T1R-B02
- 1,060 ft/lbs torque capacity
- 122% greater torque capacity than OE
- Twin ceramic friction surfaces
- 225 mm / 8.8-inch clutch disc diameter
- Solid rigid chrome-moly Mono-Drive hub
- Heavy Duty pressure plate
- Puck-style ceramic friction plates
- High coefficient of friction
- Superior heat capacity
- Lightweight rigid construction
- Predictable aggressive engagement
- Light pedal effort
- Rapid shifting capability
- Possible start-off judder
- Moderate to increased transmission gear noise
- CNC-machined and dynamically balanced flywheel
- Forged aluminum cover
- Patented Monoloc Collar
- Fully rebuildable modular design
- Designed for Drag, Road, and Rally Racing
- Clamp-load tested, balanced, and SFI certified
Specifications
| Specification | Details |
|---|---|
| Brand | ACT |
| Part Number | T1R-B02 |
| Item Description | ACT Mod-Twin 225 Heavy Duty Rigid Race Clutch Kit |
| Product Weight | 33.1 lbs |
| Torque Capacity | 1,060 ft/lbs |
| Torque Capacity Over OE | 122% |
| Disc Material | Ceramic |
| Clutch Disc Diameter | 8.8 inches / 225 mm |
| Input Shaft Diameter | 1.375 inches |
| Pressure Plate Type | Heavy Duty |
| Recommended Use | Drag / Road / Rally Racing |
Performance and Durability
Feel: The ACT Mod-Twin 225 HD Rigid Race clutch delivers predictable aggressive engagement, light pedal effort, and rapid shifting. The rigid hub design may produce start-off judder and moderate to increased transmission gear noise depending on the vehicle and drivetrain configuration.
Life: The forged aluminum cover, rigid chrome-moly Mono-Drive hub, specially treated diaphragm spring, premium ceramic friction materials, and hardened wear points are engineered to withstand demanding racing conditions while providing long service life.
Quality: ACT combines robust construction, strategic engineering, premium materials, and close manufacturing tolerances to provide high heat tolerance and maximum performance in severe racing applications.
ACT Difference: ACT applies tactical engineering to the Mod-Twin platform to address common compromises associated with twin-disc clutch systems. The result is an ultra-durable, customer-serviceable clutch with very high torque capacity. ACT clutch assemblies are clamp-load tested, dynamically balanced, and SFI certified.
Break-In Recommendations
ACT race discs generally require only a few controlled hard slips to properly lap the friction surfaces before normal driving or racing. Avoid overheating the clutch during the break-in process, as excessive heat can cause friction surfaces to fuse together, create hot spots, or glaze the friction material.
Frequently Asked Questions
Are ACT clutches balanced?
Yes. ACT clutch assemblies are computer spin-balanced to within 0.25 oz-in to help ensure smooth operation throughout the RPM range. Stock production clutches are typically balanced to within approximately 0.50 oz-in.
Will an ACT clutch increase pedal effort?
ACT pressure plates are designed for high-torque applications. Depending on the application, Heavy Duty pressure plates can increase pedal effort by approximately 15–40%, while Xtreme pressure plates can increase pedal effort by approximately 50–80%. The additional clamping force helps provide greater torque capacity, durability, and engagement performance.
Do ACT race clutches require a break-in period?
ACT race discs generally require only a few controlled hard slips to properly lap the friction surfaces before normal driving or racing. Avoid excessive heat during this process.
Are ACT clutches repairable or rebuildable?
The ACT Mod-Twin is designed as a modular and rebuildable clutch system. In some situations, repairs or rebuilding may be possible following inspection of the assembly. Due to the specialized construction and modifications involved, ACT recommends servicing by qualified technicians familiar with Mod-Twin systems rather than a general clutch rebuilder.
How much does the ACT clutch weigh?
The ACT Mod-Twin 225 HD Rigid Race clutch assembly weighs approximately 33.1 lbs and is generally comparable to the weight of a stock OEM clutch assembly.
