November 2009
Performance Auto Sound Magazine
A full review of the Racing Beat Exhaust System.
The Racing Beat REV8 "street legal", cat-back RX-8 exhaust system for the 2004-08 RX-8 is the perfect replacement for your stock exhaust - a durable assembly offering a real horsepower gain over your stock unit. This extremely popular RX-8 system consists of 304 stainless steel Racing Beat connecting-pipe, muffler canisters, tubing, flanges, and outlet tips. The replacement connecting-pipe is manufactured using 3-inch (OD) tubing and features cast stainless steel flanges for positive exhaust gas sealing. The stainless steel muffler canisters are each finished with 4-inch, polished 304 stainless tips for an aggressive look. Hand-crafted in-house by Racing Beat, each REV8 muffler is welded using our specialized welding fixtures to ensure accurate fitting on each RX-8 chassis.

Power Output
Utilizing our in-house dyno test facilities, the Racing Beat engineering staff has undertaken exhaust system extensive testing with the RX-8 Renesis engine. Our research has found that simply adding a large-diameter, "straight-through" muffler is very loud, and power gains are only modest. We focused our development efforts on optimizing the power output, while maintaining a moderate, but aggressive exhaust tone.
Based upon our initial test sessions, it appeared that the Mazda engineers did not leave much "untapped" horsepower behind in the stock exhaust system. Although it appears there might be modest power gains available from a "cat-back" exhaust system, be wary of big horsepower claims from any aftermarket exhaust system.
Our testing has provided the following results:
Stock production engine - with muffler removed +5 HP
Stock production engine - with RB muffler + 3.5 HP
Stock production engine - with aftermarket system "A" muffler + 3.5 HP
Stock production engine - with aftermarket system "B" muffler + -1.5 HP
For a report on our testing methods, follow this link.

Sound Quality
Takayuki Oku, Racing Beat's co-founder and chief exhaust designer, has spent considerable time and effort in an attempt to fine-tune the internal canister design of our muffler canister to provide what he believes is the ultimate rotary exhaust note!!! As he notes, "A little bit of my blood, sweat, and soul is in everyone of these RX-8 mufflers!" During development of the exhaust he worked extensively to find the optimum balance between power and sound level. Too much sound dampening would rob power; too little dampening would bring the exhaust note up to unacceptable levels.
Just what is "unacceptable"? We assume that an individual that has purchased a RX-8 is seeking an exhaust note that reflects the character of both the car and the maturity of the car owner. The exhaust note that we envision for this car should provide a modest sound level increase over stock, but any harsh or "tinny" tones should be suppressed. Cruising speeds should not produce any droning or buzzing tones, but provide a deep melodic tone that doesn't distract from the driving experience. But, jump on the throttle and the exhaust should come alive with an aggressive note that enhances the driving experience. Refined and modest while cruising; aggressive and authoritative under acceleration - that is the balance that we strived to achieve!