The Blackline limited slip differential for the 1986- Porsche 944/Turbo—Audi-Porsche BV 016/093/Audi A4 Quattro rear—also known as an LSD (limited slip differential), improves traction by distributing torque between the two drive wheels based on available grip.
Its helical gear design allows the limited slip differential to transmit more torque to the wheel with the best traction. As torque increases, the gears exert pressure against the differential housing and generate the internal friction necessary for this torque distribution. The system can thus handle a significant difference in traction between the two wheels, particularly during heavy acceleration out of a turn or when traction is limited.
Under light loads, the helical limited slip differential maintains smooth, progressive, and quiet operation. The wheels can continue to rotate at different speeds when necessary, particularly when cornering. This feature enhances traction during spirited driving while maintaining handling suitable for everyday road use.
The Blackline limited slip differential uses a parallel-axis helical gear architecture optimized to distribute forces. Its 5:1 torque split means that when one wheel loses traction, the wheel with the most traction can receive up to five times the torque transmitted to the spinning wheel.
As with any helical-gear limited slip differential, a minimum amount of resistance must remain on the wheel with the least grip to allow torque transfer. Its effectiveness is therefore optimal when both wheels retain a minimum amount of resistance.
The Blackline HLF181 limited slip differential is designed for the 1986 and later Porsche 944/turbo, Audi-Porsche BV 016/093, and Audi A4 Quattro rear-wheel drive models. The number of splines is a critical factor to check before mounting in order to select the version compatible with the vehicle’s drivetrain. Its housing and gears are made of high-resistance 8620 steel.
Technical Specifications of the Blackline limited slip differential for Porsche 944/turbo (1986–), Audi-Porsche BV 016/093, and Audi A4 Quattro (rear)
Manufacturer Part Number: HLF181
Quaife application code: QDF4Q
Type: Helical-gear limited slip differential
Porsche compatibility: Porsche 944/944 turbo 1986–
Porsche Compatibility: Porsche BV 016/093
Audi compatibility: Audi BV 016/093 - A4 Quattro rear
Torque split ratio: 5:1
Housing and gear material: High-resistance 8620 steel
Mounting: Direct replacement for the original differential on compatible vehicles
Key Features of the Blackline limited slip differential for Porsche 944/turbo 1986– / Audi-Porsche BV 016/093 / Audi A4 Quattro (rear)
- Torque split between the wheels based on available traction.
- Delivers more torque to the wheel with the best traction.
- Immediate and progressive reaction to changes in traction.
- Smooth, progressive, and quiet operation.
- No friction discs for reduced maintenance requirements.
- Power delivery that is easily controllable, especially during spirited driving and drifting.
- Housing and gears made of high-resistance 8620 steel.
- Direct mounting for the original differential.
