The heart of our Racing Beat Power Pulse muffler for the 1999-2003 Miata (auto transmission) is our polished 304-stainless steel canister. The inlet and outlet tubes also feature mandrel-bent 304-stainless steel for excellent durability and appearance. For maximum performance potential, our muffler features the same 2.375" OD Straight-Flow internal design configuration as our RX-7 Turbo II exhaust systems. Finished with a 3.5" OD polished 304-stainless steel tip, this large diameter muffler will handle applications from stock to race.
Designed entirely by Racing Beat, this muffler features stainless steel wool and ceramic sound-deadening packing insulation to provide the optimum exhaust note for your Miata. The Power Pulse Muffler offers a deep, throaty exhaust note without any harsh, buzzy or droning tones. All Racing Beat's exhaust are tuned in-house by our engineering staff to produce a modest exhaust tone at low speeds, and a bit more "attitude" under full throttle acceleration.
On an otherwise stock 1999 Miata (baseline hp - 110.6) our dyno tests have shown a 2.4 hp gain (max hp - 113.0) with the addition of this muffler. Combine this muffler with a Racing Beat air intake for gains of up to 8.5 hp! Don't be swayed by exaggerated performance claims made by other aftermarket suppliers - big HP gains from an aftermarket rear muffler simply don't exist. If they did, why would Mazda leave this untapped horsepower behind?
Each Power Pulse muffler is supplied with a replacement OEM donut style gasket. Installation can be completed using basic hand tools; simply unbolt the two retaining nuts, slip the original muffler off the rubber hanger grommets, and then reverse the process for installation of the new Power Pulse muffler. The Power Pulse muffler is 50-state emissions legal and meets all California sound level requirements.
Muffler Fitment on Auto Transmission Models
Due to ongoing discrepancies with regards to the mounting flange bolt-hole spacing on automatic transmission cars, we are suggesting that you measure the flange bolt-hole spacing prior to placing an order. (Why Mazda decided to use a different flange on the AT version has left us baffled! Sorry for the extra work required to determine the correct exhaust for your application, but we'd rather have you order the correct muffler and avoid the hassles and expense of returning the wrong part.) If you have any questions about these measurements, please give us a call for assistance.
We request that you measure the flange bolt-hole spacing on your car to confirm that you will be obtaining the correct muffler for your application. The measurement of concern is the spacing of the bolt holes on the flange between the muffler and the connecting pipe section.
Note your measurements as follows:
Automatic Transmission - 3.46" (88mm) center-to-center Manual Transmission - 4.33" (110mm) center-to-center
If your measurements match the specifications for "Auto Transmission", then you have selected the correct product listing.
If your measurements match the specifications for "Manual Transmission", then you will order Power Pulse Exhaust Part No. 56461.
Application:
| Year | Make | Model | Trim |
| 1999 - 2003 | Mazda | Miata | Auto Trans |