cat removal on an ATX?
- Thread starter andrea
- Start date
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rendyx
New Member
Probably a muffler shop would saw them off for you and put in a steel pipe. Or, you could saw them out, but I don't know what to put in their place. Good luck!
Mr Anonymous
Tire Wall
Not likely in CA (where she's from)!!! eek!
It would be hard to do yourself due to the angle that the pipes enter the cats on the ATX. You might be able to find a shop to do it out-of-state though... (Although doesn't CA visually inspect cats???)
Mike Kopstain
New Member
A muffler shop wouldn't touch that job with a 10 foot pole from the next county.
Andrea, go out to your toolbox, get your grinder, and cut a door into the bottom of each cat. Pull out the insides and then go tell your mechanic that you ran over something that tore a door into each of your cats. He should weld it shut for you.
Andrea, go out to your toolbox, get your grinder, and cut a door into the bottom of each cat. Pull out the insides and then go tell your mechanic that you ran over something that tore a door into each of your cats.
He should weld it shut for you.I realize it's super illegal, but I am almost positive my cats are bad... unless somebody has a good ATX y-pipe that they could sell for a reasonable sum to an underemployed poor computer tech?
It's only until I have the cash to replace the y-pipe anyway...
It's only until I have the cash to replace the y-pipe anyway...
Speedy_91_SHO
New Member
To get around the visual inspection you could get a fake cat. My friend got straight pipes on his and didn't want it to look illegal so he got "fake cats". They look real and we will see if they work on visual, he goes to court tommorrow for a "loud exhaust" ticket. He went to a car stereo place and had them stand 50 feet away and they gave him the paper stating how many Db's it was thumbs_u .
BlackMagik
New Member
I just went through this and here's the cheapest solution for bad cats:
Step 1. Drop y-pipe off of car (this is also the hardest part because the bolts will be hard to remove...clean all bolts thoroughly and use any socket that fits best among standard or metric). Expect to break at least one exhaust stud. If you do break one you'll have to drill it and tap it...which can be done on the car with a snake-equipped dremmel and very sharp/new bits.
Step 2. Go to Sears and get a $5.OO set of diamond rotary cutters for your dremmel and cut off the top heat shields of the cats.
Step 3. Use the dremmel to cut out the box shape in the converter (once you get it off you'll see what I mean). Only cut three sides completely through and one side partly. This allows you to open the square piece like a door and makes it easier to weld back straight. Then extract the ceramic chunks clogging the y-pipe.
Step 4. Bend the doors back down and have a local machine shop weld them shut with a mig welder.
Step 6. Re-install the y-pipe using all new bolts and nuts (stainless is highly recommended) and check for leaks. More than likely the gasket between the y-pipe and the flex pipe will leak even with a new gasket. Don't even bother with a new gasket just take it to the muffler shop an have the ****** cut off and a straight piece welded in...leak proof.
Step 7. While you are at the muffler shop have them weld on a new cat in a straight section of the exhaust (the resonator section is a good place to do it because the resonator is expendable). Heck, you should be able to get two in that section with little trouble.
Now you've spent less the $2,200 for a new ford Y-pipe and less than a new $500 aftermarket pipe and you have a legal car that is no louder than stock (the loudness usually comes from the bad ****** gasket). I spent $80 for a new cat install, $20 for new stainless hardware, $10 for drill bits, $10 for dremmel cutters, and $30 to have the ****** cut off and a straight section welded in. I think the total came out to be about $150 and I'm legal emissions and noise.
The worst part of the whole process is it's time consuming!
Hope this helps!!!!!
Step 1. Drop y-pipe off of car (this is also the hardest part because the bolts will be hard to remove...clean all bolts thoroughly and use any socket that fits best among standard or metric). Expect to break at least one exhaust stud. If you do break one you'll have to drill it and tap it...which can be done on the car with a snake-equipped dremmel and very sharp/new bits.
Step 2. Go to Sears and get a $5.OO set of diamond rotary cutters for your dremmel and cut off the top heat shields of the cats.
Step 3. Use the dremmel to cut out the box shape in the converter (once you get it off you'll see what I mean). Only cut three sides completely through and one side partly. This allows you to open the square piece like a door and makes it easier to weld back straight. Then extract the ceramic chunks clogging the y-pipe.
Step 4. Bend the doors back down and have a local machine shop weld them shut with a mig welder.
Step 6. Re-install the y-pipe using all new bolts and nuts (stainless is highly recommended) and check for leaks. More than likely the gasket between the y-pipe and the flex pipe will leak even with a new gasket. Don't even bother with a new gasket just take it to the muffler shop an have the ****** cut off and a straight piece welded in...leak proof.
Step 7. While you are at the muffler shop have them weld on a new cat in a straight section of the exhaust (the resonator section is a good place to do it because the resonator is expendable). Heck, you should be able to get two in that section with little trouble.
Now you've spent less the $2,200 for a new ford Y-pipe and less than a new $500 aftermarket pipe and you have a legal car that is no louder than stock (the loudness usually comes from the bad ****** gasket). I spent $80 for a new cat install, $20 for new stainless hardware, $10 for drill bits, $10 for dremmel cutters, and $30 to have the ****** cut off and a straight section welded in. I think the total came out to be about $150 and I'm legal emissions and noise.
The worst part of the whole process is it's time consuming!
Hope this helps!!!!!
andrea,
I’m San Mateo near the new Franklyn Campus. You won't find a muffler shop that will do the work. I'm sure I can find someone but the cost will be $$ compared to just getting a used Y-Pipe.
Why do you think they are bad?? My 84,000 mile SHO just passed emissions with 1HC@ idle and 1HC@ 2500RPM. That was with the original Y-Pipe and O2 Sensors.
I’m San Mateo near the new Franklyn Campus. You won't find a muffler shop that will do the work. I'm sure I can find someone but the cost will be $$ compared to just getting a used Y-Pipe.
Why do you think they are bad?? My 84,000 mile SHO just passed emissions with 1HC@ idle and 1HC@ 2500RPM. That was with the original Y-Pipe and O2 Sensors.
sdpatt
Sr. SHO Engr.
Does California require the measurement of the nitrides of oxygen (NOx)? My car is having a difficult time meeting the requirement here in Texas.
sdpatt,
Not yet. I'm being told that in July all cars will need to be checked on a rolling Dyno to create a load. Also at this time all ODB2 cars "96 up" will have a Computer scan for and CE codes. I don't total believe the date yet because most shops don't even have the rollers installed. Santa Clara County is already checking for codes so I know its coming.
I'm pretty sure that when we switch to the new ODB2 System that NOx will also be checked.
Not yet. I'm being told that in July all cars will need to be checked on a rolling Dyno to create a load. Also at this time all ODB2 cars "96 up" will have a Computer scan for and CE codes. I don't total believe the date yet because most shops don't even have the rollers installed. Santa Clara County is already checking for codes so I know its coming.
I'm pretty sure that when we switch to the new ODB2 System that NOx will also be checked.
KentuckySHOoff
New Member
being from cali and it is illegal for you to do i would invest in a high flow cat.
billh
New Member
Lets say, just theoretical of course, that you had a friend who happened to own a muffler shop and would gladly remove your cats and weld in a solid piece of pipe. And, further more, you lived in a part of Washington State that didn’t do emission inspections. Still theoretical of course. Would removing the cats:
A) Give any extra power?
B) Affect the sound? (Having the car sound like one of the P.O.S. Honda rice grinders around here would be the ultimate horror)
Anyone had any experience here?
Theoretical of course.
wink
Thanks
A) Give any extra power?
B) Affect the sound? (Having the car sound like one of the P.O.S. Honda rice grinders around here would be the ultimate horror)
Anyone had any experience here?
Theoretical of course.
wink
Thanks
KentuckySHOoff
New Member
i had my cats removed, there is definately a different feel when accelerating (smoother) as far as dyno goes don't really know the #'s but more flow usually means more power. But if you don't like your exaust to cackle leave them on, the feeling is great but the sound has to be loved.
BlackMagik
New Member
Most shops will gut or remove your y-pipe cats as long as you agree to let them install a replacent cat in the straight section at the time they modify the y-pipe cats. I'm told it doesn't matter so much where the cats are...it's just that they need to be there. This keeps them and you from getting into potential trouble.
My muffler shop warned me agains totally removing the y-pipe cats even if I put a cat or two in the straight sections because the bends in the y-pipe are so tight that there was a big chance that the new welds would not keep proper allignment and might actually break....i'm not a welder so I guess they are right....so I opted for the trap door method.
Result: Smoother power delivery, 2.5 mpg better, no rasp at all, no more full throttle only starts, no more gravel in a can noise at idle, and maybe a few db louder but not much.
<small>[ March 03, 2003, 07:17 PM: Message edited by: BlackMagik ]</small>
My muffler shop warned me agains totally removing the y-pipe cats even if I put a cat or two in the straight sections because the bends in the y-pipe are so tight that there was a big chance that the new welds would not keep proper allignment and might actually break....i'm not a welder so I guess they are right....so I opted for the trap door method.
Result: Smoother power delivery, 2.5 mpg better, no rasp at all, no more full throttle only starts, no more gravel in a can noise at idle, and maybe a few db louder but not much.
<small>[ March 03, 2003, 07:17 PM: Message edited by: BlackMagik ]</small>
KentuckySHOoff
New Member
i didn't have any cats and some cheap magnaflo mufflers and my car was extremly loud, prolly the mufflers, but there was very very little cackle until i had the cats removed. my car was much louder then the sho's that i have heard with straight pipes.
RStalveyARFF
too many shos
actually, you're supposed to get the cats as closest to the manifolds as possible. The hotter the better for them to work correctly.
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