tomke92z

Member
I have a 1992 Discovery 1 200TDI with a boost pin and boost ring. I love the car, but I really hate the smell of its exhaust fumes. I know it might sound crazy to some of you, but I'm considering installing a universal Euro 4 catalytic converter. Has anyone ever tried this? What could the consequences be? Can I expect the fumes to be any better? I suppose so...
 
If you can smell the exhaust fumes inside the vehicle while driving you have a big and dangerous problem.
Is your tail pipe in the original location?
Fitting a cat might change the smell from your exhaust but you're still breathing in carbon monoxide.
I'd fix your problem in safer ways before thinking a cat will fix it.
 
Sorry, I haven't made myself clear enough. I don't smell anything inside the car; I only smell it outside, but I still hate it. I park my Disco in a parking space in my residential area, and children often play next to my parking spot. Whenever I start my Disco or come back from somewhere and they are there, I feel kind of guilty about producing all those fumes right next to them.

So basically, I want my Disco to be less invasive to the environment and people around.
 
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Sorry, I haven't made myself clear enough. I don't smell anything inside the car; I only smell it outside, but I still hate it. I park my Disco in a parking space in my residential area, and children often play next to my parking spot. Whenever I start my Disco or come back from somewhere and they are there, I feel kind of guilty about producing all those fumes right next to them.

So basically, I want my Disco to be less invasive to the environment and people around.
Tbh pretty much all 200tdi chuff out some black smoke from cold starting, even without the boost rings etc.
 
Maybe time to get a battery car. These are old vehicles that were ok when they were built.
The fumes that we breath in these days, is nothing like 30-40-50 years ago, when buses, trucks and taxis belched out black soot, more people used coal to heat their homes.
Today's air quality is miles better than it used to be.
 
So, you have an old diesel which you have made worse by modifying the inj pump and are now feeling guilty about its emissions.
Perhaps it's the wrong vehicle for you.
Incidentally I don't like the smell of diesels either but unfortunately it goes with the terrority.
 
I’d reinstate the original injector and ensure the engine is fully serviced. But ultimately you won’t get around it being a 30+ year old diesel. It will never be a euro4+ engine.
 
So, you have an old diesel which you have made worse by modifying the inj pump and are now feeling guilty about its emissions.
I’m not too worried about the emissions. I know it’s an old diesel, and there’s not much I can do about that. I just hate the smell of the exhaust fumes, and I’ve always hated it, even before I adjusted the pump.

Tbh pretty much all 200tdi chuff out some black smoke from cold starting, even without the boost rings etc.
True, I don’t notice any difference in the smell after installing the boost pin and boost ring.

I want to install a catalytic converter to reduce the smell around the car—it would be great if it were at least a bit less strong. Improving emissions would just be a nice bonus. I mainly use this car for holidays and weekend trips, often camping in nature, so it would be nice if the exhaust smell were a little less intense.

My question is essentially whether anyone has done this before and what the potential consequences for the engine might be.
 
Yeah, installing catalytic converter might change/lower smell form your exhaust, placement will be crucial for ideal operating temperatures and etc.
But there will be a drawback, your EGT will go up it will act as a restriction in your exhaust, you have boost pin and ring, adjusted pump so your EGT’s are higher than stock ones so with additional restriction (that will be a cat) it will put more thermal stress on turbo and engine internals. So putting catalytic converter on 200tdi is pointless in my opinion.
 
Iirc export 200tdi had egr as an option, and also maybe a DOC cat.
300tdi had DOC cat from late L reg early M reg onwards, so maybe you could bastardise a 300 DOC downpipe as a relatively cheap test.
 
Iirc export 200tdi had egr as an option, and also maybe a DOC cat.
300tdi had DOC cat from late L reg early M reg onwards, so maybe you could bastardise a 300 DOC downpipe as a relatively cheap test.
My 98 reg 300tdi Disco has no cat.
"Since 1993 it has been a legal requirement for all petrol cars to be fitted with a catalytic converter. This also became compulsory for diesel cars in 2001. "
So no diesel Disco 1 ever needed to have one for the regs. It was NOT compulsory. You can, or could, buy CAT delete downpipes both solid and flexi.

However, what about fitting a sports exhaust?
Might blow the smell further away.
(Joke. 🤣 )
 
The cat doesn't need to be LR specific, the choices of what cat to use are limited only by the imagination of the welder installing it. As for the smell, yes, it will make a difference, I recently decatted my TD5, and itsmells like a "real diesel" now, whereas before it's exhaust scent was far less noticeable. At the extreme opposite end of the scale, my ex-wife's Citroen C5 3.0 v6 HDi almost smells like a cleaning product, and absolutely nothing like a diesel. I'm not sure if her C5 is a euro 4 or euro 5 model, as it's 2009, so could be late euro 4 or early euro 5. But, yeah, you'll get the results you want, scent-wise at least However, since you're introducing a restriction to the exhaust that wasn't there previously, you might want to look for a bigger cat than you'd expect to use on a 2.5 diesel, with the aim being to minimise the adverse effects on performance and economy. Maybe have a look at cats from 06-09 7.5 euro 4 era tonne trucks? I believe the Daf LF of that era used the Cummins 4bta, a 4 litre engine, so it's cat would be bigger and accommodate more flow, or looking at it the other way, present less restriction, than a cat for a 2 to 3 litre engine.
 
My 98 reg 300tdi Disco has no cat.
"Since 1993 it has been a legal requirement for all petrol cars to be fitted with a catalytic converter. This also became compulsory for diesel cars in 2001. "
So no diesel Disco 1 ever needed to have one for the regs. It was NOT compulsory. You can, or could, buy CAT delete downpipes both solid and flexi.

However, what about fitting a sports exhaust?
Might blow the smell further away.
(Joke. 🤣 )
My M reg 300 had a DOC cat, my R reg 300 had a DOC cat, they were std fit, so if yours has not got one someone has replaced the downpipe, which is a cheap job.
Early 10p td5 also had a DOC cat, not sure on later 15p models.

I think even modern euro 6 still have DOC cats fitted as part of their after treatment systems.
 
My M reg 300 had a DOC cat, my R reg 300 had a DOC cat, they were std fit, so if yours has not got one someone has replaced the downpipe, which is a cheap job.
Early 10p td5 also had a DOC cat, not sure on later 15p models.

I think even modern euro 6 still have DOC cats fitted as part of their after treatment systems.
Not arguing with you, simply stating how it was. I was the third owner maybe the original owner specified he didn't want the cat, maybe he or his successor replaced it, dunno.
My 2000 MY D2 TD5 also doesn't have a cat, again I am not the first owner so have no idea at what stage it was taken off, always passes emissions part of the MOT with flying colours. When the tester takes it out to test the brakes he always says what a nice drive it is. Maybe that is because it goes a bit better not having to push the gases through a cat!

Anyway this is all very interesting. Having two without cat never realised they were fitted as standard so early. ;)
 
Not arguing with you, simply stating how it was. I was the third owner maybe the original owner specified he didn't want the cat, maybe he or his successor replaced it, dunno.
My 2000 MY D2 TD5 also doesn't have a cat, again I am not the first owner so have no idea at what stage it was taken off, always passes emissions part of the MOT with flying colours. When the tester takes it out to test the brakes he always says what a nice drive it is. Maybe that is because it goes a bit better not having to push the gases through a cat!

Anyway this is all very interesting. Having two without cat never realised they were fitted as standard so early. ;)
I have replaced them with std plain downpipes, and have to say I did not notice any difference, but I was young and full of ideas!
As I have gotten older I have realised you simply cannot beat standard spec for reliability.
 
I must admit I hate the smell from my 300tdi, I think it seems more obvious as modern cars are so clean. I find the same smell in rural France as there are so many older diesels. Try a company who specialise in catalytic or emission treatments, they might know of something.
 

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