I've got an 06 EX Automatic Coupe. Magnaflow recently released a cat back for the car, and although it sounds great, the price is $461 and up. The only modification in the system from stock is basically a higher flowing resonator and muffler. I went a differant route. For $200 installed, I cut the resonator out completely, put on a Pro-Flo twister exhaust and exhaust tip, and basically got the same power gain ,(if not more), and saved some money for other toys. Here are some clips.

http://media.putfile.com/Twister-Ove...Civic-Coupe-18

http://media.putfile.com/Twister-Ove...-Civic-Coupe-2

http://media.putfile.com/Twister-Ove...-Civic-Coupe-3

http://media.putfile.com/Twister-Exh...utomatic-Coupe

I don't know that it sounds better, or even as good as the Magnaflow. The power gain is just as great though, especially in the mid-range, and that is what I was most concerned with. I think it would be hard to beat for the money, considering I spent more for my CAI then I did this mod.

 

im pretty sure the magnaflow catback also come with larger piping which also helps air flow. i dont think they would use the same size piping for a performance catback. i have the fujita f5 intake, what about you. i love mine and it sounds great. your pics didnt work.
what size piping did you use to run basically your own axle back exhaust system. can you feel a diffence in power, cause i agree on saving money. i was gonna bend my own 2.5" catback and fab it myself, and put a magnaflow muffler on it.

have you been able to run against anyone yet?

 

I had to run the ActivX controller and update Quicktime to get them to run. Kind of a pain, but it sounds good for the money he saved. I aggree with koonce though, you probably get bigger piping plus the fact that it is mandrel bent (and it has probably been researched on a dyno) would give you a little more power.

 

Guys, I know what your saying, but hard as it is to believe, the piping is the same diameter. If you go to Magnaflow's site you can view a diagram of the system and you will see what I'm saying. Also, they have not released any dyno info to date on either system available( both EX or SI coupe.) The place I had do this mod is an authorized Magnaflow dealer, and he looked it all over and recommended doiong what I did for both power and money reasons. I had the cash to do the Mag cat back, and thats what I was going to have done until he told me I would be getting more for my money out of this. There is no way a high flow resonator and muffler is going to flow better than just eliminating the resonator altogether and putting on a strait through muffler. Magnaflows so called cat back is really just an axle back system. Also, yes I have noticed a considerable gain from doing the mod. I already had the Fujita intake which was a noticable gain, and the exhaust mod just made it better. I wish I knew a place to go have it put on a dyno to see how many ponies I've released, but I know its way better than stock. I'm thinking of just eliminating the cat altogether and running 3" pipe from the headers to the exhaust.

 

Scratch the end of that post. Running no cat and 3" pipe would be a big mistake I've found after more research. I would end up burning up the valves and losing a lot of low end power. 2.25" pipe is the ideal pipe for the 06 Civic with a high flow cat, so thats what I will be doing to finish it up. It already has 2.25"pipe, but not mandrel bent, so I will get the cat installed and replace the stock pipe with a mandrel bent one of the same size.