I currently have my turbo being repaired, and so have good access to the front cat on my TD6. Some have advised me to 'break up' the honeycomb inside it so as to avoid it failing in the future and also to give better performance. Is this something I should consider? I have concerns over what, if any, faults this will give rise to because of O2 sensors etc. If anyone has experience of this mod I'd appreciate your input. Living in SA, there are no concerns over emissions restrictions or MOT type tests.

I'd say knocking its guts out should do the job but not upset any sensors from others that have done the job on the TD6.

Also if you got the cash think about replacing the section after the cat where it splits into 2 and the back box

There aren't any O2 sensors or any other sensors for that matter in a TD6 exhaust system so you can remove the guts of the pre cat and the cat without any concerns, things can only improve if you do.
Must be nice not to have to worry about MOT's

Thanks guys - well its out with the broom handle this weekend then... Hopefully some better performance in store once refurbished turbo back in and cats sorted - also new breather, air filter and EGR blanking. Will report back .

Good morning. From the other perspective, we have a relatively modern TD5 and we removed the cat, fitted an egr blank and chipped it. Yes the thing is now more responsive and for me thats great
But, my wife hates it as it now smells like an old 1970's ice cream van,(unburnt diesel fumes as the cat does'nt burn them now) it smokes on heavy throttle use and she says it now sounds like a tractor with a noisy exhaust!

Ive recently purchased a FFSC and had the cats removed as one had a minor rattle, now when that starts up from cold it also smells like a car from the precat era (unburnt fuel again). A much nicer exhaust note now, better fuel economy and goes faster.

So, please think carefully about this before you do it as once you've destroyed the cat "with the broom handle" then its done! You have to live with the consequences "warts n all" and a cat is a pricey item to replace...

One last point... I had a cat replacement pipe made for my SC with flanges (so i could refit the cat) as i was unsure how loud the car would be and for MOT purposes . I also sold my cats complete for scrap and they sold for more than the whole job cost me from start to finish, so... Result!!!

Regards Craig

Thanks Craig. good advice. I'm not sure what the local scrappy market is like in SA for cats, but even so your idea of fitting flanged pipe sections as replaceable parts is a good one.
Graham

Graham,

Scrap is scrap the world over... I guess if you research it you should find a decent company paying fair prices. I was offered as little as £30 for my two cats and sold them to a cat recycling company for over £250 for the pair...

They welded flanges to my replacement pipe but not the cats as i did'nt think i would need to refit them, but i had them do it so flanges could have been added to the cats to refit if i was unhappy with the results...

Craig

now you'll have everybody stripping their cats out and taking them to the scrappies craig..  ... - .- -.




Y. O. L. O.
.

Just remember that it appears that as of 1 January 2012 the MOT in the uk will require the cat to be in place at the time of mot for all cars that had them fitted at manufacture.
As I understand it they won't test them for anything, they just have to be there.
Otherwise it's a fail and an expensive replacement.

I believe thats why they are being stolen so offen Scarey!

Craig

funny you should say that craig, i'm sure i read somewhere that these thief's easily crawl under 4x4's and saw them off... ... - .- -.




Y. O. L. O.
.

Well, when they are worth as much as a set of stolen wheels its far less effort i guess!

Craig

Quick update as promised. New Turbo is back in, and cats removed. I must say that I dont see significant change in performance, but I was told that the turbo was over boosting before I had it repaired, so perhaps the performance gain I got from removing the cats was offset by the turbo not delivering quite so much output. In any case, I'm happy as now I dont get an awful squeel evert yime i pull away. Thanks everyone for your input.

Thanks for the update