Stoptech 127.34078L Disc Brake Rotor - Rear Left

Overview of StopTech Sport Cross-Drilled & Slotted Disc Brake Rotors

The StopTech Sport Cross-Drilled & Slotted Disc Brake Rotor (Part Number 127.34078L) is engineered for BMW 323i, 325i, and 328i models. Designed to enhance braking performance, this vented rotor features a slotted and drilled surface to improve heat dissipation and maintain consistent stopping power under demanding conditions.

• Compatible with BMW 323i, 325i, and 328i models
• Part Number: 127.34078L
• Vented disc brake rotor with cross-drilled and slotted surface
• Coated hat finish for corrosion resistance
• Overall diameter: 299.8 mm (11.803 inches)
• Nominal thickness: 20.0 mm (0.787 inches)
• Discard thickness: 18.4 mm (0.724 inches)
• 5 lug holes with 120 mm bolt circle diameter
• Weight approximately 6.25 kg (13.75 lbs)

Detailed Product Description

This StopTech Sport Cross-Drilled & Slotted Disc Brake Rotor is specifically designed for select BMW models including the 323i, 325i, and 328i. The rotor features a vented design with straight vanes to optimize airflow and reduce heat buildup during braking. The cross-drilled and slotted surface helps to evacuate gases, dust, and water, improving brake pad contact and reducing the risk of brake fade. The coated hat finish provides additional protection against corrosion, extending the rotor's service life.

With an outside diameter of 299.8 mm and a nominal thickness of 20 mm, this rotor meets OEM specifications for fit and function. The 5-lug hole pattern with a 120 mm bolt circle diameter ensures proper mounting on compatible BMW hubs. The rotor’s overall height is 66.2 mm, and it includes a center hole diameter of 75 mm for precise alignment. Note that this rotor does not include an ABS tone ring or bearings.

Applications and Problem Solving

• Improves braking performance for BMW 323i, 325i, and 328i vehicles
• Reduces brake fade during aggressive driving or track use
• Helps prevent rotor warping caused by excessive heat
• Enhances pad bite and braking consistency in wet conditions
• Addresses corrosion issues with coated hat finish

Installation Notes and Tips

• Ensure compatibility with BMW 323i, 325i, and 328i before installation
• Check rotor thickness and discard limits (nominal thickness 20.0 mm, discard thickness 18.4 mm)
• Use proper torque specifications for the 5 lug bolts on a 120 mm bolt circle
• Inspect brake pads and replace if worn to optimize rotor performance
• Clean rotor surface before installation to remove any protective coatings or debris

Quality Assurance and Warranty

StopTech Sport Cross-Drilled & Slotted Disc Brake Rotors are manufactured to meet or exceed OEM standards for durability and performance. The coated hat finish provides corrosion resistance to extend rotor life. While specific warranty details are not provided here, StopTech products typically come with a limited warranty against defects in materials and workmanship. Always consult the product documentation or manufacturer for exact warranty terms.