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Discussion Starter #1
I looked at the magnaflow and CPE. Former looks like $$ for little gain and latter looks like too much $$ and noise. It would appear that the best bang for the buck would be to replace the rear section with a single muffler and take out the kink in the flow. Does anybody sell such an animal? I searched around, apologize if this has been discussed before.
 

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Nope. Those two are the only complete solutions on the market right now. Your best bet would be to go with a custom job from a local exhaust shop.
 

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This setup shouldnt be too expensive to custom make it. A single muffler and then it spilts into two out the exhaust. Shape the pipes oval to match the rear bumper insert.
 

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This setup shouldnt be too expensive to custom make it. A single muffler and then it spilts into two out the exhaust. Shape the pipes oval to match the rear bumper insert.
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Problem with this, unlesss you don't mind it loud, is where to put the single muffler. It would have to be in front of the rear axle (unless you had the muffler where one of the stock one is now and then curved the the other pipe all the way back to the other side, which would be really weird), and there isn't any space in front of the rear axle to put anything substantial.

I've been under the car looking at the exhaust routing with the muffler shop that did mine. You could put a long skinny resonator style (ie. straight thru) cannister about 16" long just before the rear axle, but it couldn't be more than 4" in diameter unless you want to seriously decrease the ground clearance by letting a larger one hang down.

Also, the MS6 is surprisingly LOUD. A single, straight thru resonator won't do much to quieten it down at all, single or dual outlet. Check out people's experiences with the CP-E system. It's essentially a single outlet with a small resonator style muffler as I describe above.

Best bang for the buck, as surmised by sloopercat, is to take out the T junction, both mufflers and put in a single muffler. But, depending on the muffler used, again it may be quite loud. Anything quiet would be more restrictive, canceling out some of the gains. But at least there is more space behind the axle for a more substantial muffler.
 

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I have a CP-E downpipe going into a Borla Oval muffler, then into a resonator that came out of an Apexi cat-back for an RX-7, then straight into a turndown before the axle. Sounds mean when I'm on it, and quiet when I'm not. The resonator is straight through and the muffler is straight through with a "V" through the length of the muffler. All welded and no bends.
 

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Discussion Starter #6
Hard to believe that nobody has done a system to just replace the back part. I could care less if it only exhausted out one side. I could see just putting some black mesh in the holes and running the pipe out the side/rear corner or directed under the bumper. Those ports might work well for another set of rear lights or backups, hmm.....
 

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I think everyone wants to go with a wider diameter pipe if they decide to spend money on exhaust. It doesnt really make sense from a performance and financial standpoint to just change out the back part.

Since its a turbocharged car, everyone wants to fit a 3" down there. Or at least something wider than stock.
 

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Discussion Starter #8
Looks like the Magnaflow does not do much more than a decent rear system would do. I have no insight as to what everyone wants. It is just way too quiet, I just want to hear the engine run.......
 

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Looks like the Magnaflow does not do much more than a decent rear system would do. I have no insight as to what everyone wants. It is just way too quiet, I just want to hear the engine run.......
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If you want more noise, go to a good, local muffler shop and have them do a 3" cat back, with a single muffler. It will give you plenty of sound, and will probably be a bit cheaper than the CP-E. If you don't mind even louder, delete the second cat. This should get even more flow.

I had my shop do a 3" catback, and even with adding two Magnaflow resonators on top of an Aeoturbine muffler (I don't want it loud, opposite of you), my overall costs were still less or equivalent to the MSRP of the CP-E. Not knocking CP-E at all, just that with limited funds, adding shipping (being Canadian), and the issues with noise that some were reporting, I figured it would be more economical for me to do a custom. To take a CP-E and add a muffler and another resonator would have made that system another $250 more expensive, not including labor.
 

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I thought CP-E came out with a 3 piece design that is quieter?
 

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I thought CP-E came out with a 3 piece design that is quieter?
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It's an option that adds about $150 to the price. I don't know of anybody that's tried it yet. Others have cut out a section and added their own muffler to the original CP-E system to quieten it down a bit.
 

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Discussion Starter #12
I do not want loud, like CPE, I want decent sound like what is reported from the Magnaflow, just seems like $$ overkill for something that could be satisfied with just a new rear section. Maybe the thing to do is to replace the two rear mufflers with something a little more sporty.

Is the stock cat back pipe 2.5" or 2.75"?
 

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I do not want loud, like CPE, I want decent sound like what is reported from the Magnaflow, just seems like $$ overkill for something that could be satisfied with just a new rear section. Maybe the thing to do is to replace the two rear mufflers with something a little more sporty.

Is the stock cat back pipe 2.5" or 2.75"?
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2.5". 2.75" is a rare and unusual size AFAIK. My muffler shop recommended just cutting the stock pipe just forward of the T to reuse the section just after the 2nd cat, build a Y pipe and put in two 2.5" inlet Magnaflow mufflers where the stock ones are now. I realize now that was a wise suggestion; it probably won't flow quite as well as a 3" pipe but I'm not sure of what the actual performance difference would have been. This would have effectively duplicated the Magnaflow catback system, but possibly flow a bit better as I think they would have done a better Y junction and "straighter" bends.

Price-wise it would have been reasonable, inline with the Magnaflow catback system but completely installed, depending on which mufflers were chosen (the fancy polished stainless vs the plain stainless for example). Going with only one muffler (single outlet) may not give quite as much sound deadening as two. It would be cheaper though, as there'd be less fabrication (no Y pipe needed, one less muffler and the piping to it, etc). So it's a trade off in sound level vs cost whether to go to mufflers or one.

You could retain more of the stock system and just replace the mufflers, but keep in mind that the stock T is quite restrictive, and reduces further in diameter there, so that I believe it's only 2" going into each stock muffler. I have the mufflers downstairs (I kept all of the stock catback system in case I wanted to go back) so can measure the inlet dia if you're interested.

I wanted as much performance improvement as I could get so stuck with 3".
 

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Magnaflow also makes mufflers with 3" inlet/outlet. If you are custom fabbing... why not go all 3" piping, custom "Y" into two mufflers in the stock locations? Add a reduction pipe to the muffler outlet to connect it to the stock tips/bumper outlet and it should flow better than stock and the Magnaflow sytem, but be quieter than the CPE single outlet.
 
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