what size cat?

[reed1285]

ive searched and couldnt find a whole lot that was helpful. Im fixing to replace the WHOLE exhaust system on my 95 sr5. Everything but the crossover pipe. That includes the front pipe, cat, and an LCE exhaust system.
The system thats on my runner now is in very rough shape, its a whole custom one piece unit, all the way from the tip to the crossover pipe its one big piece, no bolts anywhere. I went to order my catalytic converter yesterday and noticed that you can order two different sizes for 2nd gens, a 12.5 and a 17.5 iirc. seeing as how my current exhaust is custom, IDK which size to order. from what ive gathered so far the 17.5 seems to be the more common. Was the 12.5 used on the 4 cyl or something? so does anyone know the deal with two different cat sizes and which one I will need for my exhaust? If not, would somebody with a stock exhaust on there v6 2nd gen measure their cat for me? thanks in advance!

 

[Hyde802]

Mines a 17" **

** aaaah I kid.... I dont know the difference. Im no help. Sorry.

Buuuut, without replacing the crossover pipe with a set of headers, anything else you do the exhaust is just noise. The crossover is where the pinchpoint of this exhaust system is.

 

[BucknutBob]

I second Hyde's comment--without replacing the crossover pipe, it won't matter what you slap on behind it, because that is THE source of restriction in that system. As for the cat, just get an aftermarket model that's designated as high flow/performance. But seriously, if you want realistic gains from your exhaust, you NEED to get headers first.

 

[reed1285]

I forgot to mention that i know im not gonna be gaining anything big from what im doing. I realize that i need headers to get a good gain from an exhaust system, but thats outta the question right now. The reason why im doing this is because emissions. I was warned last year when i did emissions that i wouldnt pass two years in a row. When i say my exhaust system is crap, i mean its CRAP. The tailpipe is cut off right behind the muffler so it exits halfway down the runner. The muffler is pretty much just a rust bucket. It sounds awful. Idk how i passed last year but i did. Anyways thats the main reason im doing a new full exhaust, not to try to gain any performance. I am however going to go with a high flow cat and the lce system.

Maybe in another year or so i can afford the 6-800 price tag for a set of headers

 

[BucknutBob]

Gotcha. It sounds like someone did you a favor on your last inspection, or the emissions output only needed the cat working to get a decent reading--mufflers don't reduce emissions.

 

[crawyota]

i'm in the process of replacing my exhaust from the down pipe back ,the cat I ordered I think is about 13" with 2" od inlet/outlet (magnaflow $68.00 0n ebay) . the muffler is a Trush Turbo muffler ($40 .00 on amazon.com)