I talked to my exhaust guy today and I think that I'm going to end up going with a 2.25 test pipe. Here are my questions. I know I'll throw a code. I need an O2 simulator.

What have you guys heard and what do you reccomend?

Thanks in advance.

 

I recommend getting a high flow cat instead. It would then be street legal and won't sound and smell like shit

 

i agree with tobra. isn't the GS-R your daily driver? screw the test pipe.

 

Won't sound like shit. I don't sit behind my car and smell it so I can't speak to that.

supposedly a 1K Ohm resistor inline with the black wires will trick the ECU. Not positive this will work on a secondary O2 but it does on a primary.

You won't notice any real performance with a test pipe over a hiighflow cat. why 2.25? 2.5 would be better no?

 

My exhaust guy talked down High Flow cats like you wouldn't believe, he didn't even think it'd be worth it in my case.Yes it is my daily driver. I have a resonator in my muffler that will keep it quiet, if I can handle the smell of a RSX, I can handle the smell of a test pipe .


My primary O2 will be fine, only the secondary I'm worried about. I've heard a few things about the ECG O2 Simulator.

I think that in my situation a test pipe would be most beneficial. I trust this guy, he's done exhaust for years. Why 2.25? The collector on my Comptech header is 2.0 and my Comptech cat-back is 2.25. Should I go 2.5 .

Oh and not to mention he is going to make my test pipe for $10.00 .

 

Based on your other parts 2.25" is fine. But 2.5" is proving to be the real power maker. You should consider a 2.5" collector header and 2.5" exhaust (Custom since 63mm is the largest brand name size I know of before 3").

A test pipe won't make more than 1 to maybe and it's a big maybe 2 hp over a high flow cat. If any power at all. the cost is the true justification.

 

The only thing that I'll be upgrading my header with at this point is a turbo manifold and downpipe . I like my Comptech stuff, and as proved by the "Great Header Test" it performs just as well as anything with a bigger collector. So based on my situation, where my only modifcations are bolt-ons, I feel like my bottleneck is the cat. I'm not going to be replacing either the header or the exhaust so I thought that a test pipe would be a good next step. Don't get me wrong I'd love to upgrade those parts, but it's not something that is feasable at this point. With cost indeed being the true justification it's looking like it will be cheaper to go with a test pipe and o2 simulator than to buy a CarSound High Flow cat.

 

:squint: It seems to me that this exhaust guy is really not a Certified "Exhaust Guy" if he said that, sounds like a un-educated back alley mechanic if you ask me.

Replaceing/Modifying Catilitic Converters is illigal.

 

He's been doing exhaust for almost 20 years. He is very reputable. He basically just told me that it'd be fairly worthless for me to do, as it doesn't free the flow up all that much, just bigger piping.

And as for the legality, I did it myself .

 

Screw a test pipe. You're not going to make any power unless you open up the exhaust more than it has been done already and if you're planning a turbo then you should just get a 3" Carsound cat when the time comes.