Do more expensive hi-flow cats preform better than ebay ones, cause theres a huge price difference. I just purchased a greddy sp2 catback and will soon get a y-pipe or possibly headers. The problem is, my max came with the ypipe,cat, and aftermarket catback all welded together, so i cannont reuse the cat.

The specific one im looking at is this one, since it has a 2.5 diameter and its SS.
http://cgi.ebay.com/ebaymotors/XTUNE...44897159QQrdZ1

 

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I have it, its nice for the price. I only use when I dyno though.

 

probably gain about 2hp.. its probably gutted out and i duno if youll pass emissions with it.

 

It's basicly a resonator. Makes the exhaust a little bit louder. I like the exhaust quiet.

 

still got the g35 muffler?

 

In my trunk now, it's up for sale, just never posted. I sounded nice, but too loud for me. If I had stock bpipe or ypipe it would be perfect.

 

Only get a new cat if your old one is defective, you will not gain much HP and you will fail emissions with the test pipe.

 

I need a new cat since the old one is welded together with my old exhaust setup. Im not looking to gain any hp, i just need something to connect the ypipe to the b pipe. How come i wont pass emissions, arent hiflow cats street legal?

 

I think the Ebay ones are just test pipes, meaning that they do not do what a cat does. I guess if you have to get one go with something that is emission friendly like the Random Technology unit.

 

They originally had these "test pipes" listed as Catalytic converters. I bought one and took issue with them because they did not have a threaded hole for the down stream O2 sensor. I also noted that they were not catalytic converters as advertised. They disappeared for awhile on ebay and now they are back and the wording is test pipe, off road use, etc. It is actually a nice piece. The metal is very thick and highly polished. I drilled and tapped a hole in mine and put the sensor in. It is my understanding that the downstream sensor is not really into play as long as the other ones are working.
I may put my old converter back on some time as it looked very good inside. I just need to get all the holes drilled back out where the bolts broke off. Here in Tennessee, we do not have a vehicle inspection program and that is good and bad. But when going over to Virginia, I see as many headlights out, broken windshields as here, and vehicle inspection is big business there.
We also don't have state income tax here either.

 

I have custom maxima test pipe which is very much like this piece, and the difference in loudness is EXTREME.... its loud ... too loud... but the diference in exceleration can be felt easily... similar gains like when u put a an UP.... by the way smell of exhaust fumes sometimes pissed me off and there is no possible way that i could pass emisions w/ it.

 

thanks guys, i had no idea this was a test pipe falsely advertised as a hiflow cat.