cat swap?

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My cats are 220K old, and i want to put some freer flowing cat in thier place.
I was wondering if I could get a cat from a car with with a V8 or something and one in the place of the dual cats that I have now? Looking for a cheaper way to get new cats and higher flow.
Any Ideas?

Thanks
Kent
 

shocker

 
 
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Since you live in OK, I don't think gov't regulation should be a problem.

Look to a company like Flowmaster for some high-flow cats. Not sure if anyone has gone this route.
 
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I cut mine off and put a flowmaster 40 series on it and dumped it by the rear passenger tire. I noticed a little more power at the seat and it sounds awesome up until 3,500 rpm's then it whines like a weed wacker but it is a beautiful thing try it.
 
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the flowmaster would be great, but I was looking for a cheaper mod that might work well. If a salvaged V8 cat would work, then I could find one that might fit in a variety of places.
The idea of putting back by the rear tire sounds good, but I thought that it had to be near the engine so that it would get to a sufficient operating temperature to be efficient. If it isn't going to work as is supposed to, I might as well not put one on there.
Anyone ever try to put another cat from another car on thier truck?
 
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Jax is confusing muffler with cat - flowmaster 40 series is a muffler.

you're running a '91, which has the two cats side by side right? I read somewhere that Gingericfj80 used a dual inlet out of a dodge truck to replace both cats. Like this

http://store.summitracing.com/default.asp?Ntt=catalytic+converter&Ntk=KeywordSearch&DDS=1&searchinresults=false&N=0&target=egnsearch.asp


or you can run a single for under $60

http://store.summitracing.com/default.asp?Ntt=catalytic+converter&Ntk=KeywordSearch&DDS=1&searchinresults=false&N=0&target=egnsearch.asp


I wouldn't buy one out of a junkyard if that's what you're going for, for $60, it's best to just put a new one in.
 
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the dual inlet from the dodge might be cool, it seems like it would be a higher flow than the stock. It seems like the single cat might be more restrictive.
It might be better to just pony up the dough and get a good one.

Thanks
 

ginericLC

Wagon Wheeler!
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I did the dodge single cat. Two inlets and one outlet. I thought it reduced the power some but I wasn't comparing it to stock. I ran catless for almost 2 years prior to installing the dodge cat. Flow numbers of the dodge cat are higher than a stock 91. But that is not the primary advantage in my mind. I liked that it was flat vs. vertical. It also didn't have all those shrouds around the cat body. I hated them on my 91 factory cats as stuff would get stuck in them and they rattled. I did leave the heat shield on the bottom of the body so things didn't get toasty.
 
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ginericfj80 said:
I did the dodge single cat. Two inlets and one outlet. I thought it reduced the power some but I wasn't comparing it to stock. I ran catless for almost 2 years prior to installing the dodge cat. Flow numbers of the dodge cat are higher than a stock 91. But that is not the primary advantage in my mind. I liked that it was flat vs. vertical. It also didn't have all those shrouds around the cat body. I hated them on my 91 factory cats as stuff would get stuck in them and they rattled. I did leave the heat shield on the bottom of the body so things didn't get toasty.
did you weld in a second bung for the other o2 sensor?
 
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I've been looking for a deal on a Dodge Cat. Thanks for the info. considering that my cats have 220K on them, I think the dodge cat will be better.
Walking eagle: my truck only has one O2 sensor. I plan to change that when I am doing the cat change. It has 22K on it also.
My truck has been running rich. With any luck, this will fix that too.
Thanks
Kent
 

CJF

 
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livelarg said:
my truck only has one O2 sensor.
You sure???

Stock '91 should have two: one on each downpipe, just before the (two) cats.

Curtis
91FJ80
 

ginericLC

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I used the Dodge cat. I left both (1991) pre cat 02 sensors in the stock location. It was right after the 02 sensors that the new cat was installed.
 
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yes, it has two. thats gunna cost a bunch to replace both of those!

Ginericfj80: can you tell me what dodge truck your cat is for?

thanks
Kent
 
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livelarg said:
yes, it has two. thats gunna cost a bunch to replace both of those!

Ginericfj80: can you tell me what dodge truck your cat is for?

thanks
Kent
unless your throwing codes, or at over 90k on the original sensors, I would not replace them. Remember, sensors CAN be cleaned.

j
 
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You have to worry about O2 sensor(s). 91 should have 2 cats w/ a sensor for each cat. Need to find a place for both sensors....Your cats should be plenty blown out. You want better flow, find a good exhaust man and run duals and a flowmaster from the cats back. Sounds and breaths better, better mpg (it needs all it can get), and runs cooler on those hot summer days...A good exhaust man should be able to do this for 3 bills or so...
 
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