Where is the best place to get a good but economical mid pipe? How effective is gutting the current catalytic converter? What effects have you experienced doing either? More power, longevity, odors, loudness, gas mileage difference etc....???

 

you should check the prices of our cats before gutting one. you could easily sell it and buy two bhr midpipes

 

The odour is awful. Some people are fine with, some are not. Take a good wiff of your exhaust after a cold start and imagine it's like that all the time.

There's no practical benefit except I guess you will never have cat problems. A bit more power but not enough to feel. The check engine light will be on permanently unless you disable it via ECU tuning devices.

 

the smell doesnt bother me at all but i also grew up on two stroke dirtbikes

 

I'm going to kindly disagree with this statement in regards to the hot exhaust, oil burning dorito engines. High heat and oil are bad for cats and cause clogging, clogged cats are bad for doritos and cause premature engine failure.

 

Well I did say "no practical benefit, except that"

 

in my experience I've not been getting the P0420 CEL at all after gutting the cat. It's been like this in 2 RX8's I've had to gut due to a clogged cat.

 

Getting as much heat away from the engine as quick as possible seems to be a benefit. More so for longevity/durability, but maybe slightly for performance. Its mostly positive, except when you consider the extra pollution, smell and maybe worse sound. I actually think many cars sound better with some type of cat as it cuts down on the raspy ness. I run an OEM cat and Mazdaspeed cat back and love the sound. Going to midpipe will probably be a stepdown in sound for me. However I am still considering it to keep the engine healthy.

Do not gut your OEM cat unless it is already shot. Just buy a cheap mid-pipe.

 

I'd get a high flow cat if it's your daily driver. The odour is not nice.
I run a midpipe now for reasons listed above. However my RX8 is not a daily driver. One can run dual resonated midpipe to cut down on raspiness like RB's version.
I would say a free flow midpipe enables the engine to rev faster and smoother at the top end of the rpm range.

 

I have a completely stock exhaust but i got the eBay 100$ midpipe. Hasnt arrived yet but if you want ill update you on the sound once I install it.