Simple questions, need answers. Sorry :)

[Robb]

Ok something that is bugging me, one of those 'down the pub and everyone thinks they are right' questions.

1.Are de-cat pipes road legal if the noise isnt a factor?

2.Which exhaust systems would pass an MOT based on CO2 emmissions?

3.Do cat-back exhausts differ from de-cats because cat-backs do not eliminate the catalytic converter and what how much of a difference in power is there?

4.Are group A&N exhausts road legal? (i was on OMP website and they dont say if their exhausts are road legal, it just says what the legal noise limit for group N, 98db, how loud are they man?! Also it says to 'empty' the first cat after fitting it? Does that mean their exhausts are only cat-backs?)

5.Who does the best exhaust system? Seriously, pipercross, omp, janspeed, they all look the same


I just want to go fast and know that if i get pulled over i dont get raped bacuase i dont know the facts and i cannot for the life of me find any material online on what different systems are legal.

Appreciate your input!

 

[rlees85]

1. driving without a cat is illegal unless your car is magic and has really really low... emissions anyway. but seriously, you must have at least ONE cat. micra has two, so you could get rid of just one of them, not both.

2. no idea

3. Yes, and a few ponies, on micras best to change the manifold to get most bhp

4. never heard of that someone else can answer lol

5. i think its down to taste and noise really i dont really have a opinion on that im sure others will though

 

[Robb]

Cool cool i swear my mate has no cat on his car but im prob wrong, so a decent mainfold and catback system is what its all about.

I bought a cheap back box from max power and i think when i finally get a 1.3 i will bodge it on the end til i can afford the real thing! The backbox has an oval tip which suits the k11 so well.

 

[rlees85]

alot of people have no cats but they either put one on for MOT time or they know the guy testing it if you get what i mean

 

[K10Daz]

My K11 only had the manifold cat on and a decat pipe in the centre section and she sailed through the emissions

 

[m-hayes]

Rally cars are supposd to be road legal (MOT Tax Insurance etc) and teh MSA nise regulations for Rally cars are lower than the law requires so Group A or N exhaust is Road legal - Except when i comes to emisisons. If there is no CAT in the system then it is almost certain it won't be legal from that point of view if your car should be filled with one. Bu tha tis no different than if you take the CAT off yours.

As fo rwhich is best - yu pay your money and take your choice! But as long as you chnge the manifold they ae all going to be beter than standard :laugh:

 

[Craig]

There is actually no 'specific' noise limit for exhaust noise to fail a MOT - it is only if the tester thinks that the noise is "excessive".
Beachboy had the Group N cat back and raved about it - it is also pretty good value for money IMO.
My friend told me that if you ahve a cat and remove it then it is illegal, however I never had any problem with a decat when I went for my MOT's


Mike - where've you been??