I wanted to get a test pipe to have for the track and was going to get one made. I remembered my old cat was lying around so this morning decided to see what I could do with it. I wrestled around for about a 1/2 hour getting the old studs out. I then proceeded to punch the cat and remove all its inners. Then I went to my local automotive store with cat in hand (actually I carried it in a bag) to see if I could get a length of pipe to insert through the middle. I had read that just clearing out the cat does not give good flow.
After looking around at all the various sizes and lengths of piping I found a piece of 2 1/2 inch pipe expanded on both ends. This is important because if its not expanded it will not be a tight fit. The cat is approximately 12" in length and this piece was around 16" with about 2-3" expanded on either end. I spent about 15 minutes driving it through the cat and out the other side until the expanded part was equal on either side and a really tight fit. I then proceeded to cut each end off with a hacksaw and ground it down so that it was flush with the flange on each end.
Pictures below. I haven't tried it yet, will install tomorrow.

Note: I didn't make this to drive on the street with.

Cat1 Pic
Cat 2 Pic

 

Nice work!

I guess if you dont care about the environment like me, you could just leave it there for daily driving

 

i still wanna see what u run with the new NX setup

 

Our next Sport Compact Drag Series race is the 22nd Jun. I will be there. My Son is just finishing up his Direct Port setup and going to try it out this weekend so should be fun.

 

dude i wish my dad was as cool as you....my dad got b!itchy when i installed my intake, imagine if i was runnin n2o....

 

sounds good and if anyone looks under your car it at least looks like a cat!!

 

Mad props on that invention, it will serve its purpose.
You just gave me an idea , Ill try that on my car so I will be visiting a junkyard to see if I can pick one old one up.



1. Also where did you get this 2 1/2 inch piping?

2. alloy or steel?

When I m your age I ll be just like you a cool Dude!!!

 

Of course you didn't

 

mine too, & he almost killed me with those orange clear corners i got

 

1. I got the piping at Canadian Tire, its like a Pep Boys etc. They have all sorts of short extensions, flex joints, tips etc. Remember though it has to be expanded at both ends not just one or it won't fit tight in the cat.

2. Its just plain old exhaust steel.

3. Also, I punched all the stuff out of the cat first. Don't do that just use the pipe to push the old cat material out of the center and leave the rest in there. It will be quieter and if someone does tap the cat it won't sound hollow.