This is a hypothetical, but how would the RX-8 run and sound if the catalytic converter was removed?

Would this boost reliability, fuel economy or performance?

 

ask any of the people that have installed a midpipe.

 

That would disqualify the car from everday driving on regular roads, though, right?

I mean, without the catalytic converter, the car is not able to meet U.S. emissions requirements?

 

If you live in an area that requires emmissions testing, then yes - it won't pass. Also, if you're running NA it will be very, very loud and annoying.

 

We don't have emissions testing in Michigan anymore - we did for a while, though.

Is it legal to remove the catalytic converter for a street registered vehicle in U.S. state, though?

I thought federal law (and many state laws) required such emissions control equipment?

 

Even some midpipes have resonators plus the muffler also quiets it down.
I had my supercat off the other day and started her up just to hear the sound. It was super loud and turned it off after 5 secs. I'll take a video of it if I ever have my supercat off again.

 

I guess it's not really a hypthetical question if it's reality, is it.......

Not true. I'm NA and it sounds awesome. I get complimented all the time.

It is not street legal to remove your cat and there are state and federal laws requiring emission control equipment. However, there are also speed limits required by every state - do you always obey?

 

^bad girl....lol

I thought the midpipe was legal? Or....am I getting the free flow cat mixed up with the midpipe?

 

So, just so I understand, you've hypothetically noticed improvements in what areas...?

...performance, fuel economy, others?

(I'm also asking because it may appear that CAT failure has led to motor failure - although I'm not quite certain oif this)

 

Cat failure and removal of the cat are two entirely different things.

Cat failure with the honeycomb breaking up and clogging the midpipe may be able to do engine damage.
Removal of the cat helps airflow and won't cause any engine damage.

 

In your hypothetical world, removing your cat allows air to flow more freely through the exhaust system. More air in = more air out = faster. I would assume the hp gain is minimal, but my butt dyno says it's faster.

My fuel economy has improved slightly, but not much. Performance wise, again, my butt dyno says it's faster. I love the way it sounds and I like the smell of fuel. How's that?

 

I hypothetically love it.

 

I'd really like to hear a sound clip of a catless RX-8. Heck, I'd like to hear a clip without any kind of exhaust.

 

A straight-pipe rotary engine is violently, uncomfortably loud. Louder than any naturally-aspirated engine you've ever heard by several orders of magnitude. I had the opportunity to be around a few racing 13Bs back in the 80s that were running straight pipes and believe me, it's like god's own chainsaw - this insanely loud ripping/angry bee sound.

And driving on the streets without a cat is a violation of federal laws prohibiting the tampering with federally-mandated emissions equipment. That's not to say you'd get caught, but any cop worth his ticket book will ask to look under the car in a New York minute if he thinks he can run up your ticket.

 

Too bad I didn't have a video camera this weekend.... I had my exhaust off and we fired her up to see what she would sound like. Let's just say that it's loud.

 

Yeah it's pretty brutal without an exhaust on. When I took my midpipe/exhaust off before trading the car, I fired it up with just the hi-flow cat/mid-pipe and no exhaust. It was one of the worst sounds I've ever heard come from a car.

 

Those would've had peripheral exhaust ports, right? Would a Renesis sound different due to its side exhaust port configuration? I certainly don't recommend running without a cat on the street... just curious.

 

Lol, darn...

I'll send you a dollar if you can do it again.

 

This is an interesting thought ... I wonder if the side port Renesis is quieter because of the more circuitous path, or even louder due to the more effective cylinder scavenging.

The last time I watched racing rotaries was up at Road America this summer in the June Sprints, and all of them had some sort of racing muffler on them because they couldn't make the minimum noise standard that is something like 100 decibels at 75 feet away. Which is about as loud as a typical chainsaw exhaust is at 3 feet away. Which is to say, really damn loud.