Hey guys(and gals)

I have a 1991 Dakota 3.9L NONMAGNUM V6, Auto, 4x4. My question is: If I cut the catalytic converter off and gut it and put it back on empty will the truck run or will it throw codes and not run at all or run poorly. I know some cars wont even run without them on. Has anyone done this and if so what is your experience?? I know the legalities of this in the state of Virginia and blah blah blah.. Don't lecture me about the environment and toxins I will put out into the air because I do not care. Al Gore is a dumbass..js. Only looking for topic specific information. In the state of Virginia where I live there is not an exhaust sniffer test nor do they do anything beyond a visual inspection of the converter itself. I have already disabled the smog pump system as it failed and seized up. I blocked off the EGR hole and plugged the vacuum line that operates it. The metal line that connects to the cat converter is also plugged and sealed at the cat.

Thanks!

 

The hell does Al Gore have to do with anything? You're not very smart if you think polluting doesn't have any effect on our environment BESIDES global climate change. If you just don't care, that's different. That said, I don't care what you do with your exhaust! O2 sensor is before the cat right?, no downstream sensor so your truck will run fine.

Edit...and sorry about straying from the topic but you called al gore a dumbass and that invited discussion as far.as I'm concerned... Not that I don't agree with you..haha

 

Thanks for the reply

 

It will run exactly the same, but louder. And a little stinkier.

 

lol Thanks! Ive had a couple others on another forum tell me that it would possibly run worse if I put the gutted can back on it. ..I can kind of see that if the exhaust gas became turbulent in the empty(not str8 threw) metal oblong cannister. Im just not for sure it would matter much.. It would have to run better than it does now tho. Im assuming the cat is more than half clogged. No power, sluggish up hills.. similar signs of a clogged cat. We shall see soon enough. Ill post my results as soon as we get a day above freezing here in Virginia! It's ridiculous outside currently.

 

You will fail inspection.

 

As I mentioned in your thread on the other forum, what !I! would do would be to replace the factory cat with a high flow cat. Matter of fact, that's what I DID on my 1988 what-the-heck-is-a-magnum? 3.9 *grins*

The loss of power, while not gigantic, is due to how the reversion pulse gets scrambled by the expansion and contraction of the exhaust plumbing.

Better to put a high flow cat on and leave that in line.

Besides, on a 3.9? You won't notice the difference between a straight pipe and the Magnaflow on performance, or lack thereof.

RwP

 

The cat on my 95 was a solid ball rattling in the case. I hollowed it and never had an issue.
As for inspections... you wouldn't believe what I got past the sniffer test. Its all about running clean, aka correctly. My cutlass passed with no smog pump, computer removed, no cats, a 77 403 with 9.1:1 compression, an edelbrock cam, headers and an H pipe system. The 307 it replaced was so tired it would never have passed.

 

Around here they don't sniff anymore. But on cars older than 96 they do a visual and if the cat is removed it will fail.

 

If you are going to gut the converter, I don't believe you have to take it off to gut it. Just remove the pipe coming out of it, take a pipe, etc and punch it out. Start the motor and blow it out before reassembling the exhaust. But FWIW unless it is stopped up, its not going to help power, and from my experience most sound terrible gutted. Not sure why, but it is different then a straight pipe. (sound wise)