I was just wondering why most people recommend a cat rather than a test pipe? any info appreciated. thanks.

 

Its called the ENVIRONMENT.

 

What are advantages/disadvantages of each??

 

Cat:
-can be street legal
-emissions
-less noise

Test pipe:
-no restrictions
-free flowing
-more power
-non-street legal

 

Are you wondering about a "catalytic converter vs a test pipe" or about a "cat back exhaust system vs a test pipe" ??

People would install a test pipe to replace the catalytic converter to have a better exhaust flow, however that is no good for the environment.

A cat. back exhaust system consist of all the exhaust piping, including the muffler, from the cat. converter to the back of the car. You cannot replace the "cat. back" with a test pipe.

Hope this help a little.

 

if your caught in CA with a testpipe
you could get a fine up to $3000

 

wow that sucks.

 

Is a huge *** fine worth 1-2 whp

 

wow that's a HEAVY fine...

 

I rode in a car with no cat, and that thing stank up with fumes. I could absolutely not stand riding in that car. And can you really feel 1-2 whp?

 

if your car is turbo u'll find 20hp i think its worth it....espeically
if your already turboed and illegal

 

forced induction is another story

 

I tried a test pipe once and the fumes were so strong I used to cough everytime I stopped at a light. It was not worth it.

 

What about a free flowing aftermarket cat? Are they leagal? Will they pass inspection? Do thay make any more power?

 

Yes, yes, and yes

 

i think that if your car is obd-2 equipped or higher and you are running a test pipe it will throw on ur CEL....in turn putting your car in safety mode.....

 

another reason would be..cuz its illegal..i know thats already been covered..and not worth the fine you get....

 

Save the test pipe for the track. Plus running a test pipe will burn out your muffler packing in no time. Don't do it if you drive your car daily.

 

If you really want to run a test pipe u could throw dummy shields on it. I would just go with an aftermarket cat.

 

Free-flow cat

 

On an ITR with my header and exhaust we barely saw a 2whp difference. However, if you plan to run the car on the track, especially road course, then I'd recommend the test pipe for only those occasions. Otherwise lets keep the air clean as best we can. You may have a problem with a cat that has been run in the VTEC range for extended periods of time, i.e. speed trials or car guys 150-200 miles weekends numerous times a year. The stock ECU runs very rich in the high rpm range which isn't the best for a cat.

 

this is in EVERY state...it's a federal law, not a state law

 

Anyone make a somewhat inexpensive free flow cat that's a direct bolt on for a Spoon header (same length as JDM 4 to 1) on ITR's? If so, what company, and how much is it?

I've been running a test pipe on mine, and the noise is finally getting to me.....

 

Yes you can feel it...and I beleive it's more like 4 hp and no it's not worththe funk to me either.

 

Inexpensive cat = Jeg's 2.5" (about $50)
Direct bolt on = no, but any muffler shop should be able to fit it


I think Dave at SMS sells direct-fit Catco cats, but they're more expensive.