Exact Catalytic Converter specs for Gen3

[Jim Merriman]

Would any one have the exact Catalytic Converter specs (physical dimensions) for the Gen3 SHOs? I'm tossing around the idea on replacing my 9 year old OEM cats with a pair of performance SS cats. Maybe I should look for some universal performance SS cats to keep the costs down? What I could use are the exact measurements of these and of the rest of the pipes from the cat back. If anybody's already done the work, and has something written up with pictures it would be great to post it on V8SHO.com as well. Also, if anyone has any recommendations, I'd like to take the advice. PS. I did see the article by Tim Wright entitled "Exhaust Design and Modification" on the V8SHO website. Good, but I need more details I guess...

Thanks

 

[99V8SHO]

This car has 3 cats, the only one you can easily get rid of is the third, clean-up cat which is just south of the flex pipe. The other two are on the exhaust manifolds and cannot be gotten rid of without custom manifolds/headers. So let's talk about the 3rd cat. First of all, why are you trying to replace it with a "erformance" cat? Why not just get rid of it altogether? Do they test emissions in CT? If they do, you can still get away with taking the 3rd cat out altogether, just do what I did, and set it up so that you can have the cat in whenever you want. I had the cat cut out and flanges welded to the pipes so that the cat could be dropped whenever I choose. I had aq test pipe built to the exact length of the section of pipe that was cut out and flanges welded to that as well. I am running the test pipe now, with the cat sitting on a shelf. If I want the cat back in, it is only a matter of jacking up one side of the car and undoing 4 bolts. The pipe drops out, the cat goes in, 4 bolts reattached and it is good to go. This is my advice for the way to do this. Altogether cost me $50 cash from a shop to do the cutting and welding.
Good luck, and let me know if you have any other questions.

 

[Jim Merriman]

This car has 3 cats, the only one you can easily get rid of is the third, clean-up cat which is just south of the flex pipe. The other two are on the exhaust manifolds and cannot be gotten rid of without custom manifolds/headers. So let's talk about the 3rd cat. First of all, why are you trying to replace it with a "erformance" cat? Why not just get rid of it altogether? Do they test emissions in CT? If they do, you can still get away with taking the 3rd cat out altogether, just do what I did, and set it up so that you can have the cat in whenever you want. I had the cat cut out and flanges welded to the pipes so that the cat could be dropped whenever I choose. I had aq test pipe built to the exact length of the section of pipe that was cut out and flanges welded to that as well. I am running the test pipe now, with the cat sitting on a shelf. If I want the cat back in, it is only a matter of jacking up one side of the car and undoing 4 bolts. The pipe drops out, the cat goes in, 4 bolts reattached and it is good to go. This is my advice for the way to do this. Altogether cost me $50 cash from a shop to do the cutting and welding.
Good luck, and let me know if you have any other questions.

This not quite what I wanted to do initially. What I'd like to do is to take the two main cats out and replace them. I'd like to replace them with performance cats that are a little more free breathing. To do so, they must be cut out and the replacements welding back into this part of the exhaust pipes before they merge (Y) back into the single pipe. But to do so, I must size them correctly. I'm thinking I'll keep the third cat on, but I like your idea for that 3rd cat piece.

So now I need some help with the front cats. Does aybody have info on good SS cats, and advise on how to go about this. Diagrams and directions are welcome.
Thanks
Jim