MagnaFlow Exhaust Products Performance Muffler 4x9 Oval Universal 2.5in ID — Deep Tone, Straight-Through

This compact, high-performance muffler pairs a straight-through perforated core with two-stage acoustic packing to balance sound attenuation and exhaust velocity. Built with a 9" wide by 4" tall body and 14" overall length, it has 2.5" inside-diameter connections on each end for universal fitment. MagnaFlow designs and dyno-tests their mufflers to refine flow dynamics, and this model carries a limited lifetime construction warranty for long-term ownership confidence.

How does the 11386 change the sound of my vehicle?

The 4" x 9" oval shape and MagnaFlow’s internal architecture are tuned to produce a deep, smooth exhaust note without harsh rasp or drone. The straight-through perforated core lets gases pass freely while the dual-stage packing absorbs high-frequency harshness.

• Deep, resonant tone consistent with MagnaFlow’s signature sound
• Reduced high-frequency harshness for a smoother note
• Less restriction than many chambered mufflers, preserving performance

Will this muffler physically fit my car and how is it installed?

11386 is a universal unit intended for custom or direct-replacement installs when dimensions match. The shell measures approximately 9" wide, 4" tall and 14" long, with 2.5" ID inlet and outlet tubes; measure your setup before purchasing. Professional installation is recommended to ensure proper alignment, secure hangers, and leak-free connections.

• Body: 9" x 4"; overall length: 14"
• Connections: 2.5" inside diameter on both ends
• Best used with professional welding or bolt-on adapters for precise fit

What performance benefits can I expect from this MagnaFlow muffler?

Designed and validated on the dyno, the 11386 improves exhaust evacuation and flow dynamics compared with many restrictive mufflers. Its straight-through design reduces backpressure, which can aid throttle response and maintain engine efficiency under load.

• Optimized flow geometry to help exhaust scavenging
• Perforated core keeps velocity while reducing restriction
• Durable construction aims for consistent performance over time

Who is this for: The MagnaFlow 11386 fits drivers and builders seeking a compact, performance-oriented universal muffler that delivers a deep, refined exhaust note without heavy restriction. It’s well suited for custom exhaust fabricators, muscle-car restorations, street performance projects, and anyone who needs a reliable, dyno-tested unit with a limited lifetime construction warranty. Confirm physical dimensions and inlet/outlet sizes for compatibility, and consider professional installation to achieve the best sound, fit, and durability.