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Hello. I'd like to cut out my Catalytic Converter sometime, but I don't have a welder to weld a pipe in.

Is welding it neccisary? It is a *very* low power car...2.3L Mustang, all stock. Will clamps on the new pipe work fine?

Thanks.
 

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I have done it a few times without any problems. I have always used 2 clamps per side stagered. If you can find them you might want to try getting the heavy duty band clamp style, I used to get them at a VW parts house.

Just rember you won't pass DEQ without one.


Jordon
 

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Build it right the first time
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yes it should be perfectly fine, clamps are not bad i ran them on the entire dual exhaust system for a mild 355 that i had for about 2 yrs no probs at all :p
 

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Take the old one off, beat up the brick inside it with a tire tool until the chunks are small enough to dump into a zip-lock bag, then bolt it back onto the car. Sell the bag of guts to a recycler.
 

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Why bolt it back into the car? We don't have inspections or Cat laws where I live.
 

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BMM said:
Why bolt it back into the car? We don't have inspections or Cat laws where I live.
Because its easier to put back and looks better that a pipe with two clamps staggered on each end. :)
 

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turbo lag......yeeeeehaaaaaaw
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BMM said:
Why bolt it back into the car? We don't have inspections or Cat laws where I live.
Actually if you live in the U.S. (I dont know where Kelowna is) it is illegal to remove any emission device.
 

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2 problems

1) usually when you gut a cat..... the exhaust gets a really odd sound to it because of the expansion, then shrinking of the open chamber. It often drives the computer nuts too, wierd scavenging.

I have seen a straight pipe inserted through the cat to prevent this.

Sometimes cats have a crooked end and you can't get in there to beat the guts out.

2) If your exhaust system has enough back pressure that a single clamp won't hold a properly fitted pipe connection........ aaaaahhhhhh....... you have a BAD problem.

If you must, then YOU cut the cats out..... then take it to a shop and have a pipe bent and installed.

Some shops won't even install a pipe there because it is federally illegal for them to do it, and if the gestapo catches them...... $$$$$$$..... and they'll build a campsite at that shop forever.
 

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It works on my T-bird. The brick got turned sideways and became a major restriction, so I took a tire tool to it, removed the restriction, and bolted the shell back in place. Freed up a boatload of power, too, but it has a Y-pipe and dual mufflers behind the cat, so the cat was the major restriction even when it was working right.

The little cats up by the exhaust manifolds were past a few bends, but when they broke I just used a plumbing snake (the coiled kind, not the flat one).

The sound didn't change noticeably, if at all.
 

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xntrik said:
2 problems

1) usually when you gut a cat..... the exhaust gets a really odd sound to it because of the expansion, then shrinking of the open chamber. It often drives the computer nuts too, wierd scavenging.

I have seen a straight pipe inserted through the cat to prevent this.

Sometimes cats have a crooked end and you can't get in there to beat the guts out.

2) If your exhaust system has enough back pressure that a single clamp won't hold a properly fitted pipe connection........ aaaaahhhhhh....... you have a BAD problem.

If you must, then YOU cut the cats out..... then take it to a shop and have a pipe bent and installed.

Some shops won't even install a pipe there because it is federally illegal for them to do it, and if the gestapo catches them...... $$$$$$$..... and they'll build a campsite at that shop forever.
How is it going to drive the computer nuts exactly? There are no ODB-II 2.3L Mustangs in existance. So there is no O2 sensor after the cats to measure effeciency, the computer dosent know straight pipe from cat pipe. Computers don't have a "scavenging" sensor or measure back pressure in any way. How much backpressure do you think an engine can create? Put a slip fit exhaust on a car with *no* clamps and put potatos on the tail pipes. The pipes are not going to explode, the engine just stalls. Where is this information coming from? :confused:



Unless the cat is clogged, my advice is to just leave it be. On a stock 2.3L Mustang, I really doubt you will feel *any* difference. Don't call me a hippie or anything, but if there is like zero payoff, why waste the time/money to have more hurtful emissions? But yea, clamps will work fine.
 

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GearJamminHero said:
How is it going to drive the computer nuts exactly? There are no ODB-II 2.3L Mustangs in existance. So there is no O2 sensor after the cats to measure effeciency, the computer dosent know straight pipe from cat pipe.

Computers don't have a "scavenging" sensor or measure back pressure in any way.

How much backpressure do you think an engine can create? Put a slip fit exhaust on a car with *no* clamps and put potatos on the tail pipes. The pipes are not going to explode, the engine just stalls. Where is this information coming from? :confused:

.

:confused: Where did you come up with that stuff? :nono:
Go back and carefully read what I wrote again.

I am not going to write a book for you.

KISS...... Full throttle is NOT O2 controlled. Relieving back pressure can make full throttle operation run lean due to increased airflow.
 

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No it dosen't. I know what open and closed loop is. So don't :nono: me. When I run open header at the track I do not need to adjust my SAFC to have the same AFR that I got white tuning on the street with full exhaust (including cat!) hooked up. You want the datalogs? We are talking about a stock 2.3L 4cyl Mustang here. Even running open headers would not cause a lean condition. How is the computer going to know there is no exhaust hooked up again? You don't have to write me a book, just a paragraph. If you wrote a book, I wouldn't buy it. But you can buy mine as it is coming out in in Q3 or Q4 of 2007. :thumbup:
 
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