im looking to see which route is best.

i wanted to put on a test pipe because im about to get tuned. as for right now im boosted and wanted to get the most out of my tune without a cat.

my delema is that i want to appear that i do have a cat, is there a company that makes a test pipe that is hollow and looks like a cat too?

or

should i get a muffler guy to just make one?

the specs should be 2.5 inches because my pipes are that big.

 

what i did to my test pipe.

i have a 2.5' test pipe with the stock cat shell over it. its like 4 10mm screws and the shell comes off the cat. do a few trimming on the ends of the shell and it should bolt over the test pipe. it will tuck up when its bolted up and when you "look" to see if you have a cat, the shell is there and visible to see and assume theres a cat there.

 

^^^there ya go, just what you need. Any willing muffler shop can do the same.

 

very cleaver

 

Thats neat....wonder if its legal?
you can also punch out a cat till its hallow. ghetto, but it works

 

heat shield wrapped around straight pipe FTW

 

thats awesome...reported to thesmogman

 

awe that's messed up lol

 

haha, i did the same for my inspection last year, lol

 

People still actually think cats restrict???????? **sigh**

 

^ no but a test pipe is way cheaper than a new cat

 

 

oooo gotcha

 

eventually after the tune ill put the cat back on for a daily drive car.

 

But why take it out for the tune? Do you think it will give you more power? Cats do absolutely nothing bad or good aside from help with emissions? You'd be wasting time and $$ swapping the cat out for anything, it won't make a difference with your power

 

plus you smell your own exhausts all the time, if you wanna pretend to be in a race car its cool, but if your driving all day kinda annoying

 

i dont smell anything with my test pipe on....ever thought about restriction?? the oem cat diameter is small oppose to a 2.5+ exhaust system (mines a 3' down pipe to a 2.5 bpipe and exhaust) thats how i think/feel though..i rather not have a restriction in flow.

 

 

hmm, i could only see this being worth doing on boosted cars. For N/A, swapping in a test pipe makes only about 2 hp, plus you will get the bad smell and your exhaust will sound more raspy, especially on the down shifts

 

stock turbo cars come with cats... The idea of removing them is just stupid.

 

deetz: i dont recall smelling any fumes when i run a test pipe. my car as well do not make a raspy sound when down shifting...i run 4-1 itr header with 2.5 outlet to a 2.5 test pipe to my 2.5 bpipe out the back..before i had the header 2.5 to a stock cat with the 2.whatever diameter connected to the stock bpipe flange welded to my 2.5 exhaust and it was restricting..it sputters before it goes smoothly..then i took it to the muffler shop and installed my 2.5 test pipe and had them re-weld the stock flange to a 2.5 flange/pipe to my 2.5 bpipe..when all said and done, i got on it and the response is quick.

also run it on my turbo car and no restriction there.

but thats just my experience, maybe its different for some other people.

 

I lost more than 2hp with a cat on my B20Vtec. Cats do restrict. I have seen it on dynos and have personally felt the difference.

I still run one though. I daily the car and have noticed a reduction in the smell emmited by the car with the cat installed.

 

Not really, Drive a bone stock WRX (which I once had) and then take off all of the cats. The difference is pretty drastic.

I speak from experience, people out there might not like or agree with taking off cats but the truth is that they are restrictions. They may not do too much on mostly stock engines, but build an engine for power and then see how much a cat holds it back.

 

all i said was STOCK TURBO cars do come with them. Yes, on built motors, they do restrict, but in Cali, you just gotta deal with it or tickets, and personally I would rather deal with a very minor power loss then tickets.

 

I have opted for that as well, even though my car is modded, I put a cat on it to damper some of the emissions. Ideally, if I had the cash, I would daily a bone stock anything instead of the hatchback.

I guess I'll enjoy my old Betty until it really gets way too hot to drive her around. Until then, I'll putt putt to work and I nice drive at night or up the coast every once in a while will do. When money allows, Track Time! Woot

Edit: back to the topic, you can also just try to get a hold of an aftermarket cat, hollow it out, and run a piece of pipe through it.