Hello I'm new to this forum and in the spring I'm going to be buying my first car, an RX-8. Now I read the introductory threads and it suggests that people don't buy this car as their first car but my mind is set. Anyways I have been doing a lot of reading up on the car and body work and performance upgrades, and I don't really know much about cars so I'm somewhat confused.. One thing I can't really understand is the difference between a cat-back, midpipe, "cat", headers and all that. I also don't really understand the order they go in. I've done a lot of searching and the reason I'm interested in these things is so when I do buy this car I'd like it to sound smooth and cool, but I also don't want it to be to loud for SCCA autoX, or to be against their rules. I was hoping someone could help answer some or all of these questions..

 

A catback exhaust is everything after the catalytic converter, a midpipe would be used to replace a faulty catalytic converter or simply to allow the flow without any restriction

 

Engine - > Header - > Catalytic convertor/midpipe - > Cat-back exhaust.

Replacing your cat with a midpipe will give you a Check Engine Light that can be masked using a cobb access port if you have a 04-08 car. It is federally illegal to tamper with emissions devices like the cat but lots of people still do. A midpipe will make the car louder.

I don't really know scca rules at all, so I will leave that to someone else.

 

Ok thanks that gives me a lot better understanding of what each is and the order lol.. still curious though about if I would be allowed to race with a midpipe because i thought I read somewhere that I couldn't.. not sure though. I'm in Milwaukee, WI. If anyone has an answer that would be great in the meantime I'll keep searchin the web. thanks again for all your help!

 

Can anyone tell me if it's ok with SCCA rules/regulations to have a midpipe..?

 

Read the SCCA rule book or post up in the RX-8 competition section.

 

If SCCA mandated that all cars be emissions compliant, probably about half the field would be disqualified.

Read the rulebook, it's right on their website.

 

As others have stated, if you want good answers about SCCA specifics, the Race forum is the right place to get informed answers.

But, I'll give you a quick answer - the two most likely classes you will run in are C-Stock and STX.

In C-Stock, you cannot change the mid-pipe it (and the cat) has to be stock (along with almost everything else on the car).

In STX, you still need a cat, but it can be an aftermarket unit, like the BHR mid-pipe with cat. So, a mid-pipe with no cat is illegal in STX, but a mid-pipe with a high-flow cat is legal (and is an important part of the power strategy).

Having said that, look to wheels/tires & suspension first for solo competition. Worry about power later. Even more important is to hook up with good drivers or take classes to learn how to drive fast. Your driving skills will be the biggest variable affecting your competitiveness.

Oh, and you can change the cat-back in any class. Good place to save weight.

 

Thanks for the feedback. I have driven autocross before for the past two years in a miata, so I do consider myself a "good driver." I'm just inquiring about the detail rules regarding a midpipe lol, and as far as my original questions were they were technical questions I didn't know the answer to. And just so all the posters who keep telling me to read the rulebook know, i have read the rulebook. I did not find specifics on what what I was looking for so I hoped I could turn to a professional. I plan on autoXing and racing my rx8 so I figured before I introduce my car to the circuit I could at least find out the specific rules pertaining to it.

Thank you though George your feedback it did help me.!