The MagnaFlow BRExhaust Direct-Fit Replacement Exhaust Kit 106-0246 is a bolt-on replacement system for the NA-generation Miata, sold under the BRExhaust line within MagnaFlow's catalog. It is aluminized steel rather than stainless, and the manufacturer says it was engineered to replace OEM exhaust number B69040100G. Its main pipes use mandrel bends instead of crush bends, which the manufacturer says improves flow compared with typical budget replacement systems. A cheap crush-bent pipe can look similar on the car, but the tighter, smoother bend is where this kit earns its price. Expect a sound change rather than a power gain: owners on user forums commonly report that aftermarket exhausts do not noticeably raise stock horsepower on the 1.6L B6ZE. Buy this for a tidy OE-style fit, a quieter tone than many aftermarket options, and a clean replacement for a rusted factory system, not for dyno numbers. Search terms this kit matches: 1990-1993 Miata 1.6L replacement exhaust, NA Miata B6ZE cat-back replacement, aluminized mandrel-bent Miata exhaust, and OEM B69040100G exhaust.
The multi-piece, adjustable design is what makes this practical for a home garage. The manufacturer says the kit needs no bending or welding, and that the adjustable sections let you route the system around axles, crossbars, and brackets. The box includes the gaskets, clamps, and a spring bolt kit. Owners on user forums describe the old system as the hardest part of the job, because the factory pipe can be stubborn to free from its rubber hangers. Expect to remove the crossbar to get the old pipe out, and the rear brace may need to swing out of the way. Owners who fitted the hangers near the tip also report needing help, so plan for a second person or a lift for the final hanger positions. Compared with MagnaFlow's stainless Street Series 15715 cat-back, this kit uses a 2-year warranty and aluminized steel, so it is a lower-cost OE-style replacement rather than a stainless upgrade.
The manufacturer lists this kit for 1990-1993 Miata 1.6L and 1994-1995 Miata 1.8L models. Its own product listings describe the coverage in slightly different ways, so confirm your engine size and model year with the manufacturer before ordering.
The manufacturer states that no bending or welding is required for installation, since the kit is a direct-fit, multi-piece, bolt-on design.
The manufacturer's Street Series 15715 is a stainless steel cat-back system with a lifetime construction warranty. This BRExhaust 106-0246 kit uses aluminized steel and carries a 2-year warranty, so it is a lower-cost replacement rather than a stainless upgrade.
Owners on user forums generally report that aftermarket exhausts do not noticeably increase stock horsepower on these cars. Buy this kit for fit, sound, and replacing a worn factory system, not for power.
This is a moderate weekend job for a home mechanic with basic hand tools and a jack stand setup, and the manufacturer's bolt-on design avoids any fabrication. Owners on user forums advise soaking the rusted clamps and hanger bolts before you start, and to support the rear of the system while you pop the rubber hangers off. Expect to remove the crossbar to free the old pipe, and to swing the rear brace out of the way. Check the new gaskets and clamp orientation, and then leave all hangers loose until every section is positioned, so you can align the pipe around the axle and crossbar before tightening.
