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hi guys, already done a search on this and it sems that some people have passed the MOT with no cats and some haven't, is this correct?

reason i am asking is that i have removed the cats awhile ago (and gutted precats) and was going to get round to either getting some new downpipes with some 100cell cats put in later on but never got round to doing it and just realised my MOT is due this week!!! was hoping that it would pass, but don't know if i should take in my old cats to them and get them to change them if it fails and retest them, and then take 'em out again as the car has been mapped without the cats? would it be harmful to run the car with the old cats and precats in, bearing in mind it has been mapped with gutted precats and no cats? do i trust my local mot station to remove downpipes etc for this 'procedure'? all this is in light of my beloved moneypit (not the girlfriend this time) failing the mot due to no cats!

what have others done ( wish i put in flanges so i could easily swap them but hindsight is a wonderful thing)?

i am really looking for a shortterm answer as my mot is due this week, most likely it would be cost prohibitive to take it out and retest,then put the gutted precat and nocat pipe in again, so what do people think i should do?

if it doesn't pass, rather than have the hassle of swapping just to pass the mot i would seriously consider upgrading it. i currently have a single (i think resonated ) milltek catback , so was either thinking of getting milltek downpipes with some 100celll cats in or going the whole hog and replacing the whole system with a milltek dual and 100 cell cats. i was just wondering what the best route would be as i am considering going for a 500bhp upgrade in the future and don't want to change exhaust AGAIN for that. would a dual milltek and race cats be ok for 500bhp or is it only custom work for this output? i like the one doug has at mrc. maybe a little loud but if its got over 400bhp i think the sound justifies it anyone know what doug has at all? and how do people think a dual milltek compares to dougs (for doug and those who have heard it?)and maybe a set of rs4 downpipes etc?

also gotta consider cost as well, those full milltek systems are expensive.

sorry for the long post but its late and i ramble in the wee hours.....

cheers

Ash

As long as you have the main cat in the main section, then you should be good to pass. The easiest section to change is the back section, in general. It's under the car. The downpipes are at the back of the engine, near the firewall - a real PITA to get to.

I hear that its possible to pass the MOT if you have another car available for the probe to sniff its ar5e instead... Or so somebody told me with a decatted monster powered Skyline...

I'm not sure how you can get teh MOT people to participate but there ya go!

You could get a carrot to pass the emissions test if you take that approach mate

some people weld the decat pipe in, some just put a pipe in and use clamps... what did you have done?

pipe and clamps can be good, as you can slide the cat back in if needed, rs4 cat is a bit tricky, as it has a sharp bend at both ends of the cat. so pipes would have to be right.

My niece and her partner run a workshop (for Saabs) and their MOT station will accept cars with no cats for testing but you must tell them beforehand that the car is not fitted with cats. They have never had any problems using this approach. If you present the car and don't tell them then, in all liklihood, the car will fail as the emissions have to be lower for a cat equipped car.


You don't mention whereabouts you are located, but if you are in North Herts area then perhaps there is a very local solution for you.

Paul

Edit...I've just read your other post and you're in Liverpool...so my "local solution" won't help you!
Don't know if this will help you at all...
http://www.motuk.co.uk/manual/contents.htm

If the car is manufactured after a certain date, it needs to pass the emissions test to get its MOT certificate. Or have I got that wrong ?

you need to have a mate who is an MOT tester and owns his own garrage

You're in Liverpool right? I can get a pass on it if you can wait a couple of weeks.... (I'm out of the country).

hi guys, just going to get my local mot people to look at it tomorrow, have let them know about thje decat, and they said it wouldn't pass but they said they 'will see what we can do'. so hopefully it will be ok.

to clarify, i have no cats just after the precats (thats the bit of pipe thats a bit of a PITA to remove isn't it?), i know coz doug did it at mrc (replaced the downpipes with an old customers decatted pipes) and it took ages with some of his magic spanners and a lot of grunting. actually he said it was the quickest one he ever did!

cheers for the offer mikey-s, i will see what they say tomorrow and if i don't find a solution i may be giving you a call. if i do have to put the cats back in i will prob upgrade the whole exhaust to a dual milltek system with some 100cell cats - just wondered about going for 500bhp and if this would be an appropriate exhaust?

thanks for all your help guys, will let you know what happens.

Ash

cars registered after 1994 MUST have cats fitted by law. If your local garage/ buddy or who ever can get around the system then thats their doing if it comes back at them.

well after all my worrying and fretting it seems that my beloved s4 lives for another year (mot wise that is) !!

suffice to say it passed but apparently it JUST passed the emmisions test, so it looks like i won't be upgrading my exhaust for awhile until i decide what to do with the car (500bhp or sell and go for rs4).

sorry to eveyone who might have been waiting for a second hand milltek catback, look like i am keeping it.

cheers for all the help guys, and the offers for mot and the like.

Ash

That's good news for you...and bad news for the guys waiting for your exhaust!