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New Enxhuast? no longer have to pass emissions

this may seem like a newbie question, but I'm gonna ask anyway. I no longer have to pass emissions in Connecticut because my car is over 20 years old. My car is approaching the point where i might want to think about refreshing some of the exhaust bits.

So here are my questions:
1) Would there be any performance benefit to completely eliminating the catalytic converter and going for a "test pipe"? I know it is listed in the parts catalogs as an upgrade, but due to backpressure, etc, might one actually LOSE performance by eliminating the cat?

2) If one WERE to go the test-pipe route, I know the resultant car would be much louder than a stock one. Is there any way to keep things on the quiet side?

3) If I WERE to go a test-pipe kind of route, would it be an added advantage to upgrade the headers? People don't seem too impressed with Bursch, but B&B has gone over well

4) I guess my main question is: without emissions being an issue, what would be the most effective exhaust setup?
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Current Stable: Black 07 Porsche Cayman S: FabSpeed Maxflo Exhaust; VividRacing ECU Tune; IPD Competition Plenum; 997GT3 Throttle Body; De-Snork'd.2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Silver 09 Mini Cooper S ("Mighty Mouse"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. Green 97 Volvo 850 Wagon ("The Viridian Falcon").
Old 06-20-2004, 06:24 AM
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If I where you, First get the header, I noticed it made a good difference in torque down low and more HP up in the R's, Also if you can get a header rap kit, this will help keep temps down in the engine bay. As for running with out a cat, I am doing that now and yes it is louder but I like it. If you can get a good cat-back exhaust system with a good resenator then you should be ok. Another thing you can do is remove the old cat and punch out the material inside and reinstall This will help reduce some noise because of the big empty chamber. I havent done any Dyno tests but I did not notice any power losses from removing my car. Backpressure would only be a problem if you made the DIA. of the exhaust greater then 2.5 inches. Good luck and let me know how it goes
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Old 06-20-2004, 06:49 AM
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the worst thing you could do is punch the cat out and hollow it. it will hurt performance a slight bit. The exhaust gases expand into the hollow chamber, which slows them down (bigger diameter) and they cool down, then have to cram back into the exhaust pipe to get out the. I done extensive dyno testing on that, and on the street. Using a hollowed out cat just makes the car sound crappy (my work van sounds like that because ours got clogged and we punched it out cuse we were cheap, and it runs like crap now). Your best bet would be to build your own exhaust, using 2.25 or 2.5" mandrel bent piping all the way, with a long magnaflow resonator in the middle to keep things quiet...
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Old 06-20-2004, 09:43 AM
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SFR looks good. Expensive but good ... http://www.speedforceracing.com/modindex.html
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Old 06-20-2004, 09:55 AM
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Header rap? Is that like Gangsta rap?
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Old 06-20-2004, 10:29 AM
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i'm about to sound really ignorant, but can one define for me exactly what "cat-back" means?
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Old 06-20-2004, 07:04 PM
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Cat-back means, From the cat back.
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Old 06-20-2004, 07:24 PM
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okay... well duh. But what I mean is, does "cat-back" include the cat? If you bought the SFR 2.5" or 3" cat-back exhaust, would you still have a catalytic converter?
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Current Stable: Black 07 Porsche Cayman S: FabSpeed Maxflo Exhaust; VividRacing ECU Tune; IPD Competition Plenum; 997GT3 Throttle Body; De-Snork'd.2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Silver 09 Mini Cooper S ("Mighty Mouse"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. Green 97 Volvo 850 Wagon ("The Viridian Falcon").
Old 06-20-2004, 07:30 PM
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Ok sorry, Cat back means from then end of your stock cat back. SO if you went and got a cat-back system it WOULD NOT come with a cat. Its all the piping after the cat.
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Old 06-20-2004, 07:33 PM
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what would have to be done to eliminate the cat? Just buy a resonator with the new cat-back system? There don't seem to be too many systems for sale that run right from the header to the rear of the car
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Current Stable: Black 07 Porsche Cayman S: FabSpeed Maxflo Exhaust; VividRacing ECU Tune; IPD Competition Plenum; 997GT3 Throttle Body; De-Snork'd.2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Silver 09 Mini Cooper S ("Mighty Mouse"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. Green 97 Volvo 850 Wagon ("The Viridian Falcon").
Old 06-20-2004, 07:38 PM
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Well you could go and get a High flow universal cat or get a Test pipe. Most cat back system have a resonator installed in the piping
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Old 06-20-2004, 07:54 PM
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I have an aftermarket exhaust on my car and I would like to go back to stock. If you would like to sell your muffler to me let me know.
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Old 06-20-2004, 08:06 PM
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