Borla 140990 Cat-Back Exhaust System - ATAK with Polyphonic Harmonizer

The Borla 140990 Cat-Back Exhaust System delivers the aggressive ATAK sound signature with innovative Polyphonic Harmonizer Technology for Silverado and Sierra trucks with factory split rear exit configurations. This system is designed for maximum performance while maintaining a drone-free cabin experience.

Key Features:

• ATAK muffler with Polyphonic Harmonizer Technology creates multiple harmonized exhaust notes for rich, full-bodied sound without interior drone
• 3.5-inch diameter inlet transitioning to dual 2.75-inch outlets maximizes exhaust flow and velocity
• Includes valve simulator to prevent Check Engine Light illumination
• Convertible to S-Type sound level by replacing Polyphonic Harmonizer with muffler 60679 (sold separately)
• Premium T-304 austenitic stainless steel construction for superior corrosion resistance and longevity
• Ultra-smooth mandrel bends ensure maximum exhaust flow and power gains
• Precision CNC manufacturing guarantees accurate, bolt-on fitment
• Patented straight-through and multi-core technology unleashes hidden horsepower

Application Notes:

• Compatible with factory split rear exit vehicles ONLY
• NOT compatible with ZR2 or AT4X models
• Crew Cab with Standard Bed (6'7", 157" wheelbase) requires Adapter 60706 (sold separately)
• Tips NOT included - reuse factory exhaust tips

Borla's patented exhaust technology increases exhaust velocity to add power, improve throttle response, enhance fuel economy, and deliver the distinctive Borla Sound of Power. Backed by Borla's Million-Mile Warranty, this system represents the pinnacle of exhaust engineering from the world's most experienced performance exhaust manufacturer.