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harrys
20-08-2008, 17:02
Hi,

My car has a magnex exhuast and de-cat. Ive decided to get my clio back on the road after a year being garaged up. Therefore its last MOT was over 2 years ago, and was passed with the de-cat with a lot of help from my pap and lots of begging. My problem is i want the car to get back on the road but know it will fail on the MOT. Therefore i just need to know what i need to do to get the car road worthy. Hopefully with this in mind someone could answer a few of my questions.

1) Can i just buy a normal cat and fit this for the MOT?
2) Would it be easier to just get a standard exhaust fitted?

The reason i say this is because im not to keen on how loud the magnex exhaust it and just want something quieter. Therefore i gather a standard exhaust is the only way?? Im no mechanic obviously, therefore any help would be really, really appreciated! Thanks,

16v_paddy
20-08-2008, 18:31
You can put a normal cat on no problems, will quiet it down a fair bit as well. I had to do it for my MOT

white16valver
20-08-2008, 18:33
A cat should make a marked difference to noise levels!

PM MatBrown on here as he may have one :)

number1
20-08-2008, 23:10
Had to put the cat briefly back on mine recently, was whisper quiet even with a mongoose, performance gain with a decat pipe isnt really a great deal,

Dave

16v_paddy
20-08-2008, 23:14
magnex & de-cat is purely for noise and popping on demand
I love it :twisted:

LEIGH-ANNE
21-08-2008, 00:17
where u based maybe u could borrow a cat off sumone for the MOT. I'm in Southampton anyways.

I had a magnet on mine... was too loud for me. I have a scorpion backbox with decat and is a fair bit quieter tbh

Wobba
21-08-2008, 14:12
Easy job putting a cat back on assuming the 4 bolts are not seized.

Mine does pop and bang with a magnex and decat, but rarely and no way as often as my valver with the same setup.

harrys
21-08-2008, 15:39
cheers for the help guys! Live Down in Dorset.
Yeah mine does the pop and bang etc (little flash out the exhuast). Is this due to the decat or magnex? Anyways think il go down just the cat route then, sounds simpler, and if stops the noise il be happy! Final thing, and sorry for being a little bitch and asking what are probably really easy basic questions. Is it easy to change the cat myself? Im no car mechanic, but have the tools if it aint too hard. Really appreciate all the help guys!

Wobba
21-08-2008, 17:15
Jack car up, put on axle stands, get under it with a 13mm spannerx2 or ratchet spanner and 13mm socket.

Check the 4 bolts, 2 on each end on the decat. Are they seized on? if so, this is the only problem you will have. If so, saw them off (shit job tbh) and refit new bolts/nuts ones with washers when you have replaced decat with cat.

Remember to retrieve gaskets and reuse if they are okay.

Replacing decat is same as cat. Just remember you may need to use exhaust sealant on the flanges. Holts Firegum ftw here. It's easy to have a blowing exhaust if not refitted tight enough without sealant.

Try not to move the exhaust about too much as this could result in knocks when you didn't have them before.

queegan
21-08-2008, 17:33
poping is not a good thing though as it means enigine is running to rich or to lean i thought?

16v_paddy
21-08-2008, 20:05
^^ all good cars do it, its only on the over run (letting off the throttle from high revs) dumping unburnt fuel into the exhaust

Wobba
22-08-2008, 15:54
Flameouts are even better though :D

harrys
26-08-2008, 19:50
thanks guys, finally got round to doing this, quick 10 min job! Much appreciated