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Discussion Starter #1
So when my muffler rotted out last winter, I took a look at my exhaust system and found it to be... err... thin, particularly the pipe that goes over the rear axle. I think I'm probably going to be looking at a new system this summer (or at least in the near future), and I'm looking for the following:
1. I want better performance. I'm thinking about doing a catback (I've heard that the pipe from the manifold to the cat itself is quite substantial compared to the rest of the system, although I've never measured myself). I don't want to have to pay for a new cat, either. I'm thinking either 2 1/4" or 2 1/2", whichever I can afford, mandrel bent if possible.
2. I want a better exhaust tone. I figure with the long stroke of the 2.5, I can get a decently low tone. What I really want is for it to sound like a big-block V8, with that aggressive, burbly sort of sound. I know that I'm not going to get that with a four cylinder, but I want to get as close as possible for a decently low price. I also don't want anything too loud, just for it to sound more aggressive from the curb.
3. I want the system to be durable. I know that SS is the best, but it's also expensive. Is there a coating or paint that I can put on the exhaust to keep it from rusting out? I don't want to put down money only to have to replace the system in anything less than five years.
Recommendations? Also, how much of this is possible to DIY? If I can't DIY, where should I go, a chain like Meineke?
 

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Exhaust systems rot from the inside out, due to sulfuric and nitric acid formation, so there is no coating that will help extend the life of the system. Stainless is simply the way to go. My 84 Daytona Turbo Z appears to have its original stainless exhaust on it.

As you know, sound has no relation to performance. You should decide which is your priority. Bob O'Neill put a larger exhaust on his 86 Daytona base model, I think it's 2 1/4" diameter. A larger diameter exhaust generally will give a little more power at higher RPMs, and a little less at lower RPMs, You'll want to select a size that suits the power range that you're looking for.
 

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I agree with Bob, and as far as diameter goes, the smallest spot or crimp is the actual size of the exhaust. Just because you have four inch exhaust doesn't mean it will breathe that way if there is a crimp that takes it down to two inches. Many a time the double walled tubes, in an attempt to slow the rotting process noted by Bob, the inside pipe would get crimped down to less than half the pipe outside diameter, so mandrel single pipe is best. As far as tone goes, I became very partial to the tone of the Dynomax over the other more popular mufflers, definitely has a better sound and drone than the others as far as my ear can tell.
 

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About the sound, consider running it without rearmost muffler, like I do with my T2. It will not be too loud at all even for passengers in high speeds, many have been surprised mine runs without a muffler.
About the size, in any case I think over 2½ inches for a 2.5 engine is nonsense. Like in my LeBaron T2 the downpipe is 2½ and "outlet" is 2" from the factory. That is actually engineered somehow as the gases right after turbo / manifold
are hotter than those in the end of the pipe, so the gases need more space in the beginning of the system.

dana44 said:
I agree with Bob, and as far as diameter goes, the smallest spot or crimp is the actual size of the exhaust. Just because you have four inch exhaust doesn't mean it will breathe that way if there is a crimp that takes it down to two inches..
Heh.. you've probaby seen those 1.6 L Hondas with 4" tail pipes. All show, no go... They make me laugh (about the owner) each time I see them.
 

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Discussion Starter #5
I can't run without a muffler, that's too much for me. The turbo on your convertible does help to quiet the exhaust down.
If Bob O. has a 2 1/4", that's probably what I'll end up going with, stainless if I can afford.
As for mufflers, I want performance first. I assume that a higher-flow muffler will probably have a better tone than the stock muffler anyways. I'll have to look into the Dynomax.

Bob, IIRC you put an exhaust on one of your Daytonas in the not-too-distant past. Did you do a catback or did you replace the entire system from the manifold down?
 

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Hopefully you can find a link for the tone of the Dynomax.
 

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Discussion Starter #7
I went on their website, I particularly liked the tone of the VT muffler but if the Super Turbo is cheaper, that's what I'm going to go with.
 

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When I bought the car in 2009, I replaced the exhaust from the manifold back. I used the stock system, which is only 1 7/8". It gives good backpressure, so off the line it's good. For me, the power is fine. However, next time I'd bump it to at least 2", since most of my driving is highway. I bought the carbon steel pipes and stainless muffler from Maremont (Walker), however they always rust out early - 30K to 60K miles, right at the inlet to the muffler. I do like the tone of their systems, though. The muffler was about $85 from one site, but only about $40 on a closeout from Rockauto. The pipes are cheap, so the catback is only about $130 with clamps.
 

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I wouldn't waste the money on anything larger than 2.25, which I believe is the size of the dump of the exhaust manifold itself. Remember, only as large as its smallest cross section.
 

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Discussion Starter #10
Right. What I've shifted to thinking now is galvanized tubing bits and pieces, I know you can get mandrel bent sections, in a heavier gauge, with a 2" catback system to a VT muffler. I'm thinking of using SS clamps so that I can (hopefully) disassemble the system in case one of the pipes rots. Is this better than what I have? And will I have galvanic corrosion from stainless on galvanized/aluminized?
 

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Unless someone says otherwise, galvanized doesn't handle high temps, including the caution that cooked zinc can be heavy metal poisonous, and does peel off at temperatures above 400 degrees F. Aluminized is better and can handle temperatures above 1200 degrees.
 

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Discussion Starter #12
Thanks dana, I thought they were two words for the same thing.
 

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Thank wikipedia for the temp separation points.
 

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If you are just looking for cost effective, I suggest going for the Walker stuff at Autozone or Rock Auto, have had good luck with their OEM fit stuff, and replaced from the manifold back for less money than a fancy cat-back job.

Doesn't do much to address your desire for a better exhaust note but was a heck of a lot easier and cheaper than dealing with rusted fasteners and bolts to hook up the cat back.

I doubt you will see much performance change unless you do other mods that would be hindered by the stock set up.

Just my 2 cents.
 

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SS clamps won't help, as the pipes weld themselves together and you won't be able to separate them. When the over-the-axle pipe rots as it ALWAYS does at the muffler inlet, I throw away a good muffler and replace everything from the cat back. I use a Dremel tool and heavy-duty cutoff wheel to cut the pipe just behind the connection to the rear of the catcon, then carefully cut longitudinally through the rear pipe without cutting the catcon outlet beneath it, then use a screwdriver to peel the cut open and get the stub off. Takes me only about 10 minutes. I cut the clamps, or break the shackle by torquing it off with a socket wrench. However, if you load up their threads with anti-seize compound when they're new, they will still unscrew during the first two years.

BTW, I've used and like Maremont (Walker) exhaust systems, but the last two that I bought have had a VERY sloppy, loose fit at both ends of the over-the-axle pipe, so that I had to crush the clamps on to take up slack, and still had a leak. I then plastered JB Weld epoxy around the seam, since the pipes were oval and I didn't want to replace the whole system. It's OK and leakproof, but I'm very disillusioned with them.
 

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Discussion Starter #16
I had a Walker muffler rot out in 18 months, I have another one on there now only because it was the cheapest one and was the only one in stock at the time I needed it. Bob, where can you get the bigger over-axle pipe? I want to go to a bigger system (2.5, as that's the smallest the VT muffler comes in). Also, how do the pipes weld? Through corrosion, or is it an actual weld?
 

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I haven't researched better pipes yet, I probably have 2 years left on the current system. I think the turbo is 2.0 inches, so buying a turbo setup from catback might do it. The pipes corrode together and also are crimped together by the clamps, so there's really no hope of separating them. Typically the carbon steel systems are between about $85 and $130 for all hardware back of the cat. I was once quoted $700 by a muffler shop for a fabricated SS system. Back then, I never thought I'd keep these cars so long, and since it was equivalent to the cost of 8 carbon steel systems, I didn't think it worth it. I'm now reconsidering, as it would be the last exhaust the car would ever need. And if I shop around, it should be cheaper.
 

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B10alia,
If you can get ahold of an exhaust from a like turbo car in the yard do that for function economy ($$) and economy (mpg). If this isn't possible, I bought the Dynomax cat-back through Summit Racing, totaled out less than $90 including tax; I installed it. I wasn't found of the sound but remidied that with a simple $10 dual outlet tip. It went from annoying low frequency drone at all rpm to a digestable rumbly sound. It is still pretty quiet and did experience better fuel economy.

My opinion remains that if you desire a super sounding exhaust, there is no choice as my favorite has been and will always be Borla. I am uncertain how themanage to do it but every Borla exhaust I have ever heard just sound very "performance" to HIGH performance oriented; like I stated, that is only... my opinion.
 

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Discussion Starter #19
I think what I'm going to do is have a Meineke or some shop fab me up some 2.5" pipes (smallest the VT muffler comes in) from the cat back and do the install. Couldn't find a catback on there for a '95 Spirit, pSun, can you find the link you used (I know you have a Sundance)?
And Bob, what do you think a ballpark for a fabricated SS exhaust would be? $3-400?
 

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I think the following setup will be the most cost effective setup that kinda fits what you are looking for.

MagnaFlow Direct-Fit Catalytic Converter 23251 http://www.ebay.com/itm/390548954696 $99.56
Walker Intermediate Pipe 45179 http://www.ebay.com/itm/390538288629 $21.95
Walker/Pro-Fit 43130 Connecting Pipe http://www.ebay.com/itm/370762932982 $6.95
Dynomax Super Turbo Muffler 2" Off In 2" Off Out http://www.ebay.com/itm/330866012691 $69.90
Walker/Pro-Fit 41422 Tail Pipe http://www.ebay.com/itm/370761923185 $5.95
Shipping $4.95
Total $209.26

Of particular note is the MagnaFlow catalytic converter. It is stainless steel. The super turbo muffler is probably going to be the closest thing to what you want the car to sound like as well. As for the other pipes, they are of similar quality of the original exhaust system. I've used Walker's pipes before and so far no rust.
 
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