Hey guys,
I just bought a new cat back 2.5" piping.
I am going boost in 3 weeks and I want your guy's opinion.

Right now my setup is no cat and when I go boost i need the downpipe welded.

I was thinking of getting a test pipe with the o2 sensor slot and have that fill in the gap from the missing cat. and then have the welder connect the downpipe to the test pipe.

Is the a good idea or not because I dont really know what a test pipe is for. I assume its for swapping out the cat for track use and then putting the cat on for street.

Opinions on what i should do please

 

You're right about what a test pipe does, if you have no intentions of running a cat, you could just have your down pipe bolt straight to your catback. If you want the option of running a cat at some point, get the test pipe. If you don't get a test pipe, just make sure you weld in an o2 sensor bung into your downpipe.

My setup: 3" downpipe straight into catback, o2 bung welded in.

 

Nice. That's a 94 too right?

Well, I don't plan on ever running a cat. I was just thinking removable and also it has the o2 spot on it already so i wouldn't have to pay someone to weld it in. The o2 sensor would be used for my wideband though.

Do you think the test pipe would restrict airflow in anyway?

 

The way I see it and I'm going to do it soon is,

1. Weld the O2 sensor to the oem location on your new exhaust system to ensure proper reading.
2. Put flanges both side of the cat and add flanges to the DP to suit.
3. Cut a Pipe, same diameter and material as your exhaust system, length must the the same as the cat as you're going to replace the cat with this pipe on track days.
4. Put same flanges on the pipe ends that you've just made
5. Get an old cat from somewhere and extract the housing/outer body, weld this to the pipe that you've just made.

It makes it look like you're running a cat but you actually have a straight through system with no restriction. Anyways, I think since you're in Florida, you don't have to pass emission laws so I hear.

 

yea mine is a 94. I like kccord's idea, if anybody checks under my car i'm sorta screwed for not having a cat.

 

The idea is ok until you start to pop flames on the street :p

idk, EPA crap is strict in here.

 

ya but for me we don't have emissions. So i don't plan on having a cat ever.

 

emissions checks and a visual check for not having a cat are different though. I think you can still get in trouble.

 

True..
In OKC there is no emissions or inspection to speak of, but if your caught by the police with an exhaust system with no cat there will be a ticket writen.

 

4" Downpipe, 4" exhaust. No cat.

:O)

 

I'm always **** curious of your setup, may share a link for pictures and build your highness?