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OK, heres what has happened.

Less then a year ago I had a 3" hi-flow cat supplied and installed on my 33. Now the guy at the exhaust shop ensured me that the cat was a "True hi-flow unit unlike alot of the other shit that other shops sell". He also said that it would last up to 100,000 km before needing a change. So, I agree for them to fit one on.

When I came back to pick up my car, I quickly noticed that the cat had been welded onto my cat-back exhaust without my permission. At first I was pissed off as they had not consulted or told me about this being done, but then I thought about it and concluded that the cat would not need to be changed in the next 100,000 km so it wouldn't matter. And maybe the welding of the cat would prove to be less a restriction than bolting up to the flanges of the exhaust?

So for the next 11 months I had been driving around with not a trouble from my whole exhaust system until last week. Now I started to notice a rattling from my exhaust system. After careful inspection, I had pin-pointed this rattling sound to be coming from my cat. So, being a loyal customer, I took my car over to the same exhaust shop for them to fix it.

I was told quite bluntly that the cat was f&*ked and that I would need to fork out another 400 or so dollars for a new one. F%CK!

Me: 'What about the warranty? Surely I'd be covered by it as I had only done <30k &

Mechanic: 'Sorry warranty doesn't cover modified vehicles'.

So here I am with a f&*ked cat welded onto my exhaust. Now this situation has been made worse due to me not being able to find any info, let alone warranty info, on the cat which I've been told is branded "Autosound" or something. And also that the cat is welded on, which would require more labour to get off and another one put on compared with a bolted in cat.

Now here is the Q:

Has anyone heard of the brand "Autosound" for exhaust components?

What should I do?

-Is it probable that the exhaust guy is pulling my leg about the warranty?

-Should I pursue this issue further or just cut my losses and get another cat?

-Or is there some other alternative?

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Had similar experience with a non performance car. A mistubishi express van.

Put new cat and replaced exhaust which had holes in it. It started to rattle when cold then even when hot after 25000km........apparently if the car is out of tune (ie. running rich) the cat warranty is void. The van was running mega rich tho.

Minor details which i wasnt told about.

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I had a 3" turbo back system done by D&T Performance.

Overall system quality was really good apart from the dump pipe.

The cat is apparently a 7ltr highflow cat. The internal does look quite open, not small holes like most I have seen.

Its done 90,000km's over almost 3years.

Still running fine.

http://www.dtperformance.com.au/http://http://www.d&tperformance.com.au' target='_blank'>

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Cutting it at the welds isn't a big issue, especially since it is already stuffed. Flanged cat is much simpler though. The real issue is what caused it to die so quickly, even the crappiest cat shoudln't do that. What sort of A/F ratios are you running?

As for superior cat converterss I recently tried out one of the 4" Magic cats, it worked very well, cost around $500. They don't come with flanges, so they have to be welded on, any decent exhaust shop can do it.

:D

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jd-runr,

It may be a CarSound catalytic converter.

http://www.hopupracing.com/macaca.html

Just to note my cat also has the provision for the temp probe.

I am suspecting mine is actually a Mirror Finish Magnaflow (by carsound) cat with the little D&T stamp on the bottom.

EDIT: No its not.. Looking at a few pics mine is different. :D

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I read about those..

SK - the car you put it on, was there any significant restriction in the exhaust prior to the magic cat install?

like the soarer in the zoom article?

what were your gains?

This car originally had no cat, just a straight through 3" pipe, got busted for it. Stuck a 4" Magic on it and it lost ZERO horsepower, made ~255 rwkw both ways. I have never seen that before, a cat always looses power to a straight through pipe, even the best hi flow 3" ones loose a little bit. Our dyno guy checked it twice, 'cause he didn't believe it either.

They must have an upper limit, where a straight through 3" pipe is better, but it is more than 250 rwkw, that's for sure.:D

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Could you, would you put one of these 4 inch cats in a 3 inch system?

This was a 3.25" cat back, I just grabbed a couple of cones and flanges from the local exhaust shop ~$35). Our race team fabricator welded it up, took about half an hour (say $50 at the exhaust shop). He just copied the dimensions (length) and flange alignment from the straight through (cat replacement) pipe. The guy originally wanted to keep his straight through pipe for track days, but when it made the same power with the cat in he didn't bother.:D

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  • 3 weeks later...

After deciding to check the extent of the damage to my cat, I unbolted it from the front pipe and looked inside.

The cat was stuffed alright, stuffed with a size 13 spanner. Stupid #$%^s at the exhaust shop must've dropped it in there when I took it in to get the dump pipe fitted.

The cat is fixed now with no rattling at all! Won't be ever going back to that place again.

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After deciding to check the extent of the damage to my cat, I unbolted it from the front pipe and looked inside.  

The cat was stuffed alright,  stuffed with a size 13 spanner.  Stupid #$%^s at the exhaust shop must've dropped it in there when I took it in to get the dump pipe fitted.  

The cat is fixed now with no rattling at all!  Won't be ever going back to that place again.

:thumbsup: And you get a free 13mm spanner!

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I have also heard very good reports about the magic cats.

I am planning to fit one up to my car as it has been running very very rich and it lost a few kw on the dyno which I am assuming is because it has started melting the insides of it.

Devious plug: I can get the magic cats for $450 if anybody wants one.

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how do the CATs.. or should i say.. how are the CAT recognised as a Legal device on a car....

example ..if the cop pulls u over and looks at your exhaust. doesnt see a recognisable CAT.... what happens then? bend over?

ummm or do i say test my emissions orrificer? i'm running a certified CAT!

would sorely love to install one on my car when i fabricate my new system... but more concerned bout the legalities IF any that can and may happen if u get pulled over by the law...

Thanks

Matt

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After deciding to check the extent of the damage to my cat, I unbolted it from the front pipe and looked inside.  

The cat was stuffed alright,  stuffed with a size 13 spanner.  Stupid #$%^s at the exhaust shop must've dropped it in there when I took it in to get the dump pipe fitted.  

The cat is fixed now with no rattling at all!  Won't be ever going back to that place again.

Hi rd-runr

what area are they in? just like to know so us locals can steer clear.

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