Gutted Catalytic Vs. Test Pipe

[GeorgeGerez]

I have a 1998 Eclipse GST. I would like to know if it's better to have my Stock Catalytic Gutted (meaning removal of all the inside) and placed back on the car or get a test pipe / straight pipe..


also Why do I keep reading about Ebay's $40 Test Pipe and a High Flow Catalytic. a Test pipe just replaces the catalytic. so what's the big deal? Please Pardon my ignorance.. Thanks

I live in Florida and we don't have emission tests..

 

[GSTBlack95]

It would make your exhaust a bit louder and you get a little less backpressure.

 

[BlackAWD]

I have a 1998 Eclipse GST. I would like to know if it's better to have my Stock Catalytic Gutted (meaning removal of all the inside) and placed back on the car or get a test pipe / straight pipe..


also Why do I keep reading about Ebay's $40 Test Pipe and a High Flow Catalytic. a Test pipe just replaces the catalytic. so what's the big deal? Please Pardon my ignorance.. Thanks

I live in Florida and we don't have emission tests..

Yes a test pipe/straight pipe replaces a CAT. It might be better to get the test pipe just because it will most likely be larger (3"). Larger pipe = faster car. Plus the CAT is shaped funny so I'm not sure on how that will effect exhaust flow. There are test pipes that look like CAT's and they are cylindrical inside despite the appearance of looking like a CAT.

 

[GSTBlack95]

Hmm yes I should of answerd all the questions as well, personally I would just keep the cat, gut it and not worry about spending money on a test pipe, unless you really dont care. Your going to have the same results basically. You want less back pressure as you have a turbo car.

 

[MNGSX]

I have seen car sound/ magnaflow cats for the cost of test pipes...

IMHO

Get a meagan DP

Carsound 3" hf cat

3" catback...... I like bosal for ground clearance and stock style muffler mounting and external dimensions.


The only time I'll mess with stock exhaust is with a tortch removing the whole thing..

 

[eclipseGSTud]

George, are you planning on getting a aftermarket exhaust system? It would be best if you get a high flow cat for the compromise of having performance and be emissions friendly. Not sure if you're required to have a catalytic converter in Florida, but if you don't need one then a test pipe would be best. If you're going to upgrade the exhaust then there are some downpipes that eliminate the cat. I currently have a Apexi N1 exhaust, 3" high flow cat, and megan racing downpipe for my ehaust system. A test pipe is just a straight pipe which gives better flow for exhaust fumes to leave.

 

[DSM BEEYACH]

Gutted Catalytic = high flow cat/ test pipe / straight pipe same difference. !

 

[GeorgeGerez]

Wow, Thanks for all your help.. and replies.. That does clear things out.. My current ehaust is all original exept from the cat back.. I added a 3 inch pipe without any restrictors unto a Power Effect Capsule (Basically its a tunable Backpresure muffler).. and now I want to change the downpipe to a 3inch all the way to muffer..

 

[BlackAWD]

Gutted Catalytic = high flow cat/ test pipe / straight pipe same difference. !

Wrong! High flow cat is still an active cat with emission control. a Gutted cat will no longer control emissions coming out of your car.

 

[BlackAWD]

Wow, Thanks for all your help.. and replies.. That does clear things out.. My current ehaust is all original exept from the cat back.. I added a 3 inch pipe without any restrictors unto a Power Effect Capsule (Basically its a tunable Backpresure muffler).. and now I want to change the downpipe to a 3inch all the way to muffer..

If you want 3" all the way you will have to replace the stock cat because it isn't 3".

 

[bhop]

I gutted my cat 2 weeks ago because my stock cat was dead and causing fuel consumption and rotten egg smell problems. I noticed a slight increase in power on the freeways and it's slightly louder. It also seems to have more of a "growl" when you mash the gas hard. It only took me about an hour to do it.

On the downside, i'm destroying the ozone (yes, I care) and the exhaust fumes are not a pleasure to deal with, especially in 2 hours daily of stop and go traffic (to and from work), in fact, sometimes it straight up makes me nauseous. I plan to order a hi-flow cat from Road Race on Monday.

 

[tstkl]

Yes a test pipe/straight pipe replaces a CAT. It might be better to get the test pipe just because it will most likely be larger (3"). Larger pipe = faster car. Plus the CAT is shaped funny so I'm not sure on how that will effect exhaust flow. There are test pipes that look like CAT's and they are cylindrical inside despite the appearance of looking like a CAT.

thats soooooo not true it isnt even funny,.... like im sure the test pipe would be better than the cat,... but where you said larger pipe = faster car,... NOT TRUE.... im sure you can look into this more on this site, but basically if the egts drop too much from the exaust staying in the pipe for longer (bigger pipe) than the denser air at the end of the exaust would need more pressure to push it out, creating backpressure in the exaust system, causing the engine to have to work harder to get the exaust gases out of the system, dont always get the biggest system you can if you have no intetions of ever using its full potential,... and if your worried about passing smog, which i doubt you are, but if you are worried and think that you can pass without a smog, you wont pass the visual with no cat down there, so some people put the shell of their gutted cat over the test pipe so that they have the test pipe for performance, and what looks like a cat from the outside...

 

[Camaro350]

If you have state inspections of any type I would run something that either looks like a cat or something that can be swapped in and out easily. Here in WV we have a yearly state inspection. Can't pass without a cat. Not for emissions...just for not having it.

Makes getting an inspection sticker a PITA.

 

[Sotarts]

A gutted catalytic converter will obviously cause more turbulence in flow, since removed material now doesn't take up the space that it used to. It depends on how you gut it.

In cat/test-pipe comparison, I believe that a race/straight/test pipe will provide smoother and in turn higher flow.

 

[killakev805]

The test pipe will give better performance than gutting the cat. If you gut the cat the, when the exhaust reaches the gutted cat it will open up and then when it has do go back into a smaller pipe it will create turbulence which can create back pressure. I didn't look to see your mods, but if you are not flowing too much than it won't be a problem, but if you're flowing some air it will make a difference.