Decat & Silencer Combo???

[Crazy_C]

I want to get Katt decatted but was wondering if I could just screw a silencer in the tip in order to pass MOT regs?

Has anyone done this before or know if this will work?

This is the silencer I was thinking of:

http://www.racerbits.com/catalog/MF-SIL-45.jpg


Cheers

[macca]

Taking the cat out won't fail the MOT because of the extra noise, it's the emissions and sticking one of those in won't make a blind bit of difference.

Some cars are lucky and get by even without a cat, but most don't. If it doesn't, you can either put the standard cat back in for the test or get a high-flow cat welded in to the system instead. That will increase power and still get through emissions but you're looking at about £200 to get it done.

[Crazy_C]

I've been told that they reduce emissions as well as they reduce the amount of gasses flowing out of the exhaust or something along those lines.

Hmmm, general idea I'm getting is just stick cat back in for MOT :p

Is it hard to take a cat out / in and swap with a decat pipe??


Cheers Macca :)

[nunchukhamster]

I've been told that they reduce emissions as well as they reduce the amount of gasses flowing out of the exhaust or something along those lines.

Hmmm, general idea I'm getting is just stick cat back in for MOT :p

Is it hard to take a cat out / in and swap with a decat pipe??


Cheers Macca :)

Normal method is to use a couple of v-bands. Basically, your CAT sits in the garage 364 days a year. At MOT time, you undo the 2 v-bands, remove the decat pipe from the car, insert the CAT and do the v-bands up. Once complete, out it comes again.

This is the likely route I will go with my 3" DP, but I also need part of my ECU remap to be customised to enable me to run without a CAT as those pesky Volvo engineers fitted a post cat Lambda sensor on my car as well as teh pre-cat wideband. Guy who writes the maps for my car can feed the ECU a dummy value in place of the rear o2 sensors actual reading.

Some cars can pass an MOT emissions test without a CAT, however, they should fail the MOT as the presence of the CAT should actually be checked as part of the test. I can't remember the cut-off year for this (1992 maybe?), but any car that is factory fitted with a CAT after a certain date must have the CAT in situ in order to pass an MOT. Remember also, that VOSA can do an emissions test at random vehicle tests too......

[Ang]

Many jap cars will pass an mot without a cat as emissions are pretty good, though its hard to tell.

Find a place that does a 2 week retest and you could try without and if it fails you'll have to put in a cat for the test or you could keep the cat in do the test and then remove it after, depends on how long until your mot.

[PaganPunkChick]

Crazy, my lude was MOT'd just before I bought her last year with the cat sat in the boot.

This year I forgot about the cat until I was at the MOT station, was sat in the bedroom in front of the wardrobe, she flew through on emissions, put Katt in and then worry about whether you need a cat on Katt ;)

[Crazy_C]

Heh, yeah, guess I will do that then :) Just gotta get a decat pipe for a JDM lude now, and then get to be able to get under my car to actully fit it (or get garage to do it lol)

[lambo-lude]

i got a decat pipe ..got ppl seeing my lude this weekend and if it sells i will keep the pipe for ya if u want

[Crazy_C]

Ooooooh, yes please Lamby :D *give you hug* hahaa

[Ang]

Double checked with James on the cat and he says it is a must for the mot even though it probably would pass emissions without it.

Its pot luck if they can be bothered with it really.

[Crazy_C]

Question - is there any way of making a decat LOOK like a cat??? hehee Fool the tester :D if it will pass on emissions that is :)

Cheers for the advice :D

[nunchukhamster]

Question - is there any way of making a decat LOOK like a cat??? hehee Fool the tester :D if it will pass on emissions that is :)

Cheers for the advice :D

It has been known for people to remove the contents of the CAT and just leave the casing behind. I would guess that it would sound very hollow though. So, would depend on whether or not the MOT tester gives the casing a tap with his testers mallet.

[macca]

That's quite common on GT-Four's, to gut the cat. They're cast so there's no way to tell if it's there or not.