Removing the catalytic converter

I can testify to that. I removed the Cat on my 2,5Tdci Mazda Drifter, and the overall power delivery and consumption was way better, as well as throttle response. You dont need to fiddle with the ECU either these days, just instll a mini-cat or cat fooler.
 
Removed my cat 2 years ago as it was rattling like mad, fuel consumption and performance on my 1.6 Polo is pretty much identical to as it was before decating, didn't have the R9000 odd they wanted for a new cat.
 
I'm using B50 Bio-Diesel in my 1.7dti Corsa Bakkie.

Apparently the DPF / Cat gets clogged easier with BD- my engine management light came on and car reverted to limp mode. Whipped out the Cat / DPF and now it's back to normal. It might be slightly louder and it definitely stinks a lot more...

YMMMV :)
 
isie said:
My Theory is if it really worked your car would have it as standard (Or in this case not have it) Car companies spends millions on research trying to get more power for less fuel for what if it was that simple.
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It has nothing to do with fuel consumption and everything to to with emissions regulations.
 
Unless the cat is shot I wouldn't specifically go about removing it.

How many kilometres?

I wouldn't volunteer to replace it though, considering it's upwards of R20k in most cases.
 
Electric said:
They were bsing you.
The cat is secured by a fiber mat that is compressed into the housing.
This is hydraulically pressed into position.

The monolith itself cannot loosen and rattle in the housing.
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Does the fiber mat look like ceramic, but softer? When hit with a hammer, does it disintegrate into a fine powder?
 
Segg said:
Unless the CAT is broken don't remove it

1) They contain a lot of platinum, so they'll get a fare share from scrap value
2) Engines are designed to run with them
3) It'll increase your fuel consumption - had the cat removed from our one vehicle, fuel consumption went from 11.5 to 15 per 100km, others have had similar results
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1) Not, actually very little.
2) Not really. It can do without on a diesel without using cat foolers. It is there for emissions.
3) BS, mine did not increase.
 
Claymore said:
How long do cats last? My car is on 300000km, and it was recently suggested to me that I remove it.
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Yours is long past dead. But if you don't hear something rattling or whatever it's probably burnt clean through and wouldn't make too much of a difference to you.

Beachless said:
It depends on the car some have O2 sensors in front and behind the Cat those cars often require messing with the electronics so that the fuel consumption does not get affected.
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You can keep the O2 sensor in place after removing the cat and then it won't affect your fuelling either as the ECU can compensate for the change.

isie said:
how long is a piece of string?
Mines something broke inside (sounded like a rattle when i revved) I couldn't afford a new one so just removed it.
As mentioned above if nothing is wrong with it leave as is
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Yup it's an insane thing to replace and you can be damn sure nobody is going to do it.

Would cost you less to fully mod the car (new exhaust system, remap and induction) so that it can happily run without it.
 
Beachless said:
It depends on the car some have O2 sensors in front and behind the Cat those cars often require messing with the electronics so that the fuel consumption does not get affected.
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Mine does not have this, as most, if not all, 4x4s. Might be the same for most platkar diesels as well. Petrol vehicles have O2 sensors and, to remove the cat, you have to reprogram the ECU and/or install cat foolers.

OP mentioned a diesel, did he not? Don't confuse the subject.
 
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Lord Farquart said:
3) BS, mine did not increase.
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I would imagine it's very car dependant.

Any car with lesser fuel injection that uses "static" mapping or doesn't have O2 sensors in the exhaust system would probably have some odd results as it doesn't know how to compensate for the lack of cat. This could of course be easily solved by having it properly tuned when they removed it in the first place and should really be part of the service.

To the OP - R900 sounds like a simple weld off weld on job to me and might have undesired results.
 
isie said:
exactly the Same with mine also a Polo (2.0) does VW use crap Catalytic converters?
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They generally only last for about 150 000km. So if you are over that mileage it's perfectly normal.

We should have just stuck to leaded petrol.
 
SauRoNZA said:
I would imagine it's very car dependant.

Any car with lesser fuel injection that uses "static" mapping or doesn't have O2 sensors in the exhaust system would probably have some odd results as it doesn't know how to compensate for the lack of cat. This could of course be easily solved by having it properly tuned when they removed it in the first place and should really be part of the service.
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SauRoNZA said:
We should have just stuck to leaded petrol.
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See, this is where i think we have our wires crossed. OP mentioned a diesel vehicle. Some gave him advice on diesels, like myself. You guys are referring to petrol vehicles. That is a different kettle of fish.
 
Lord Farquart said:
See, this is where i think we have our wires crossed. OP mentioned a diesel vehicle. Some gave him advice on diesels, like myself. You guys are referring to petrol vehicles. That is a different kettle of fish.
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Aaah in that case I do agree it's a whole different kettle of fish.

isie said:
At the time I'm sure it was less then 150 000Km actually im pretty sure was less then 90 000KM
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You might be quite right as I was completely thumb sucking.

I'm on 140 000km odd now and I'm starting to hear the odd pinging noises from the back telling me it's not long to go.
 
isie said:
At the time I'm sure it was less then 150 000Km actually im pretty sure was less then 90 000KM
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Mine was roughly at that :-) so yeah it seems right.
 
Electric said:
Pretty much.
We have a monolith retrieval department which cuts all the cats open to retrieve the monolith even if it is scap or not.
BASF for example normally have platinum delivered by armored guard.
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I've been inside a CAT producer's factory where they coat the substrate and fit it into the housing. What a company, what an operation.

I wish I could disclose what I saw regarding platinum delivery (imagine hundreds of kg/s of platinum at a time being delivered) straight from the mine, the systems designed to secure it and how it is dispensed. Practically had to get naked to exit the factory floor though.
 
SauRoNZA said:
They generally only last for about 150 000km. So if you are over that mileage it's perfectly normal.

We should have just stuck to leaded petrol.
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Lord Farquart said:
See, this is where i think we have our wires crossed. OP mentioned a diesel vehicle. Some gave him advice on diesels, like myself. You guys are referring to petrol vehicles. That is a different kettle of fish.
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Interesting- mine was pulled at ~160k km. This is probably way above what our domestic use engines require, but worth noting nonetheless:

Since the diesel engine is more durable than its gasoline counterpart, the required life expectancy for diesel catalytic converters is also longer than that for gasoline converters. For example, since 2004 the US EPA durability requirement for emission control systems on heavy-duty diesel engines is 10 years/22,000 hours/435,000 miles (700,000 km), whichever occurs first (previously, the requirements were 8 years/290,000 miles or 467,000 km).
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http://www.dieselnet.com/tech/cat_conv.php
 
Thanks for the feedback - I instructed them to leave it be this time around. :)
 
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