103 replies to this topic

[philwalker]

hi just read this thread and sounds like you can get a pass on a MOT with out having a CAT on a TDCI. mmm i was thinking of De Catting mine but worried about CO2 ect.

I might just get a sports Cat.

Cats do not reduce CO2. A diesel's cat dramatically reduces carbon monoxide and unburned hydrocarbon emissions. Decatting is, IMO, selfish and irresponsible - makes your car emit ten times as much CO and HC for what? A couple of horsepower? :annoyed:

Calm down dear!!

just look at what comes out of buses and trains and compare that to a decated car and there is no comparison. :shocked:

[sye01]

Good point well made!

Had MOT test a couple of days ago on my Mondeo TDCI 130 and passed with Graham's decat pipe without a mention.

As to the emissions debate I get a best of 58 mpg tank to tank rather than 52 mpg with the cat which is surely better for the environment...

[graemewelch]

sounds like your well happy with it.

[Tharkz]

I'm so torn in this matter.
I'm really really tempted to order one of Graeme's decats. It's going to get me a bit more power and a bit less fuel consumption. On the other hand it filters out 90-95% of those particles that are actually poisonus for humans to inhale (CO2 is not!). But it sounds so nice

Compared to decating the car I find it better to start by bypassing the EGR valve. After all it's only recycling a small part of that small part of particles that doesen't get properly combusted.

[thelongmile]

Can I just clarify an issue here please

LEGALLY any car built after 1994 is required to have a catalytic converter fitted

HOWEVER Many cars do not require one to be fitted to pass emissions tests

BUT Most garages only care that you pass an emissions test, and thats the way it tends to stand

BUT STILL remember, it's a grey area, Technically you are breaking the law if you don't have one fitted, but you are complying with the law in the sense that you are passing emissions regulations. So it falls into that disgusting little grey area that noone can ever agree on.

Just be careful if you get an overzealous cop!

And you MUST declare it to insurance

[ronnieg]

just a point in Northern Ireland our test is alot stricter than the one on the mainland. all cars made after 1998 have to have a cat in place or it is an automatic fail. well aslong as a cat shaped box is present at least.

Isn't it the case that Cats produce more CO2 but less of the stuff that's bad for humans?

My Silvia returns better MPG cat-less, gets on boost so much faster and is much more enjoyable to drive

As far as i know the mondeo isnt fitted with a catalytic converter as standard its just a smog catcher of sorts so it doesnt actually catalyse anything,it collects smog until hot/revving hard and then burns it off,im sure i read somewhere the newer euro 4 engines had a catalytic converter optional,im sure il be corrected?

I think what you're thinking of is a DPF (diesel particulate filter) which when revved harder does burn diesel exhaust soot off. Thats not the job of the catalytic convertor. And yes a DPF was an optional extra on the TDCi from 06 onwards