Hey guys I'm looking to get a cat back for my o5 and i was wondering what the difference was in the how loud the single tip racing beat is compared to the double. My goal is to have a beautiful 8 not one that gets pulled over for noise all the time.

 

I think you are referring to the single-tip and twin-tip REV8 cat-back exhaust from Racing Beat? I have had the single-tip cat-back exhaust from Raceing Beat on my 08 6MT since 2009 with everything else stock and it has been great so far.

RX8: Exhaust - Cat-Back Systems: REV8 Exhaust System - 04-08 RX-8 -

As far as I have read from others, this is the quietest aftermarket exhaust for RX8, which is the reason I chose it. However, it is still a little bit too loud for my taste since our engine runs around 3.8k rpm at 75mph on highway creating a noticeable "hum". Its not annoying, just noticeable. I have measured it with a smartphone App at 70mph and got 72db best.

What I really like about it is its quality. I am not an expert, but it felt to be properly made with a sound that's deep and refined. Its by far the "least loud" exhaust that will get you pulled over. Hope I am giving you the feedback that you are looking for.

Cheers

 

Have not heard the RB Racing Exhaust in person so I can't realy comment on the single vs dual debate.

I have had the RB Rev8 Exhaust (dual tip) for a few years now and the quailty is great. One of the best choices for an aftermarket exhaust for the following reasons:

1. Quality - I bought mine used and it still looks great.
2. Sound - It sounds amazing and is not ear numbingly loud (but noticeable over stock)
3. Performance - Flows better than the stock 2.25 inch exhaust (pretty sure the stock is 2.25 inch). Whenever I see the stock exhaust tips on an RX8 I think they look too small. The RB tips look great and fill in the space nicely