I have spent numerous hours looking at old post and have not come down to a conclusion other than the stock & Bonez ones are the best - however, can you please specifically tell me about the increase in noise level ?
Many thanks
Riccardo

 

I have a Bonez hi flow with a stock cat back. It has a little more low end (bass) sound to it, but is still very quiet. The mufflers are what will effect the sound more than anything.

 

I have the Bonez HF cat with a trust exhaust and the noise level is a little bit louder, but its a low tone noise. sounds deep and mean not a high pitch Honda noise. the muffler choice will have the most effect on noise so don't go with a thin pointed tube exhaust. get an oval can style muffler.

Jeff

 

I had a Bonez high flow with a Racing Beat dual tip and the noise level was only slightly higher than stock. Switching to an SMB metallic (which is one of the highest flow cats out there) increased the WOT noise levels considerably but again idle or cruise were only marginally louder than stock.

In terms of noise levels, I don't think it really matters what cat you get - the exhaust is the primary factor.

 

I'm inline with the above comments, the muffler will have the most overall affect on volume. However, after eliminating the pre-cats and going to a hi-flow main cat, the noise of the turbos spooling (whine) was louder.

 

They play quite a large role in the overall sound from my experience. Mine got a lot louder going from cat to midpipe with the same backbox.

 

^^^What they said. I have a Bonez & downpipe & the Bonez didn't change the sound much at all. The downpipe gives a nice sound when the turbos spool and the HF gives a slightly deeper tone. The nice thing about the HF is that you can weld a wideband sensor bung to the inlet pipe-which I did. You also save weight with both the DP & HF compared to the stock POS.

 

Many thanks to all
I will probably move fwd with a Bonez cat