Question for the 4.0'ers
 

Well, I've been dreading this for a while now, And I think the time has come. Ever since I got my 95 4.0 ZJ it's had a bad cat, Rattles really bad all the time, even at idle. So I gotta take it out, My muffler isn't too bad (For stock still) just some rust on the bottom.

So my question is, What kinda set ups do you guys have and what would you recommend? I live in Florida so I don't need to pass any emission tests or anything, so I'm not too worried about the Cat.

You don't even have DMV inspections in Florida, do you?

I had a Chevy truck with a 350 and dual exhaust. I used cats for a 4 liter Chevy S10 pickup from NAPA and they were cheap. They are 2 1/2" in and out. If it were mine, I'd use that cat and a Flowmaster muffler. You'll have to add a section to connect to the standard tailpipe. The cat is tiny and only about 12" long. You'll have to weld a metric nut to the pipe to run the downstream 02 sensor, but it'll work. You might not even need the 02 sensor.

Also, add a muffler hanger to the system where the floorpan kicks up behind the rear seat. It helps stabilize the system and helps to prevent leaks.

Right on, Thanks for the reply Dave, Yeah I don't have to pass any inspections or anything (Thank god).

Everyone that I know around here no mater what kind of truck/car/suv they just cut the Cat out and put like a flowmaster 44 on it and thats it, I was thinking about doing the same, But not really sure on how that will sound. I don't want to do something, then have it sound like crap.

First of all, without the cat, the PCM might get confused and give you the wrong mixtures and error messages. It's also illegal Federally. IDK how you'd get caught out of state on this, but it's possible.

Second, a 6 doesn't sound like a V8, so don't expect it to. Personally I can't stand the sound of a 4 cylinder with a razzy muffler. I just grates on my nerves. In my opinion, the Flowmaster gives you the best sound you're going to get from the 6 because it mellows out the sound as much as possible and is built solidly. The cat will also smooth out the exhaust pulses. I have to warn you though, that little cat will change color from the heat.

My boss maintains a residence in Florida and has all his personal vehicles registered there, but he has his mechanic do the NY DMV inspection just to make sure he doesn't have a problem. I've driven his Toyota Rav4 and it doesn't have a NY inspection sticker on it. IDK how that works.

Running without a cat on a 95 will have no ill effect on the PCM, it only has an upstream O2. I would not run without a cat, a hi-flow cat with a Flow Master 40 series is my recommendation.

Thanks guys! I do plan on moving up to Ohio next year so I probably should just buy a Cat and Flowmaster so that way I know I can pass if I have to :P

Whats the name of the cat you used Dave? I have connects in Napa so I might even be able to get it cheaper then you :P

IDK the part number but I was told it is a universal fit for the Chevy S10 pickup. I think it was only $45 and I bought 2 for my big honking 350 HO. This was also in 1997. My truck was an '89 Laredo short box 4X4 pickup. That thing was a tank, but it wouldn't go where my buddy's Wrangler would. That's why I finally bought a jeep! I had 33x12.5s on it and it didn't even need a lift.

Lol aright thanks, I'll do some research and see what I can come up with. Thanks y'all for the help!