Sidepipe and MOT - what's the deal

[boostwagon]

Ok i have a idea but i have no idea about UK legal regulations so hope someone here knows the answer for sure since i read different things on all the forums.

SidePipe (a.k.a. side exit under sills).

What are the rules, regulations, cat, CO, dB, MOT etc etc

Note: in my case it would be for a '96 P reg car

[grumpy]

I would guess its exactely the same as a normal exhaust for c/o ,db , cat etc , thats if you mean only the tailpipe visiable . If you mean coming out behind the front wheel and a long silencer up the side , I'm not sure . If thats the case , as long as it had a heatshield it would be ok as they are fitted to westfields/caterhams/cobra's etc .

[Deleted]

Emissions and cat regs will be the same as a standard system, the pipe has to exit away from any doors so the fumes can not enter the cabin and not be in a position as to cause injury or harm to any other road users.as for noise it is up to the tester to decide if it is too loud.

This is what the manual states about noise....'assess subjectively the effectiveness of the silencer in reducing exhaust noise to a level considered to be average for the vehicle'

And it also states that having part of the system missing is a reason to fail which is open to interpretation as to if the tester deems that to mean from the standard system or what you have fitted.

In short if you have a friendly tester than it will pass.

[composimmonite]

I had a Thrush Sidewinder sidepipe on my Triumph 1500 FWD (well this was 1970's and even flares were still fashionable !).
It was rigid fixed to sills and therefore needed a flexible section between pipe and downpipe. Make sure this is properly supported as a possible aspect MOT man might pick up on as a fail aspect.
Passengers hated the sidepipe as it burn their legs when getting in and out of the back seats if engine running. Noise was horrible with a 4 pot. The sound the TV made you think you'd get was from US V8's and turned out to be a joke on a small capacity Triumph. There again people thought taking the baffles out of their 50cc two stroke mopeds made them 50 mph faster as well ! I went to Scotland for a holiday and decided to do the 300+ mile journey home in one go during the night at high speed (no speed cameras back then). Needless to say one of the first things I did the following week was fit a standard exhaust. The drone of constant revs through the sidepipe was teeth numbing and has put me off them ever since.
So unless you have a throbbing V8 be prepared to have everybody laughing at you if fitted to an otherwise standard car the same as chavs with their 3" tail pipes on 1.0 shopping carts. Also accept you might see a picture of your car on the Barry Boys site

Paul H

[Deleted]

Oct 21, 2013 10:54:11 GMT composimmonite said:

I had a Thrush Sidewinder sidepipe on my Triumph 1500 FWD

Paul H

You can't say that without photographic evidence

[boostwagon]

Hmm ok, might be a reason we a visit to my local MoT station then to see what they say , they got a couple drifters etc that go there aswell (from which i know 2 have a sidepipe).

Thanks for the answers

[elmotheewokking]

You can just about see mine there, that passed, hasn't caused any passengers any injuries and doesn't let fumes into the cabin. Also sounds hilarious, but is a little bit too loud actually. Fully stainless from the downpipe back, 2" pipe, one 60degree bend with a 5"x14" straight through "silencer" on it that really does sod all.

[Deleted]

Hi Oli

[boostwagon]

Nice Elmo, well went to the MOT place here, sidepipes are allowed but like said above it depends on decibels (and of you have a new car pass Co). Overall everything is allowed even if that means a exit in the front wing and there are no sharp edges (also per opinion of the MOT guy).

BUT

Vosa has a slightly different approach since they say it has to exit out the back.....then again Vosa says your not allowed to put a cold air intake, decat pipe, race exhaust or any other aftermarket bit on your car either

[elmotheewokking]

Plenty of vehicles that have sidepipes from the factory. Mercedes McLaren SLR for one, Dodge Viper for another... Come to think of it, Caterhams have side exits and pass VOSA tests...

In essence, I'd be (am) more than happy to have a sidepipe with a VOSA inspector looking over the car.

[boostwagon]

true but they have it from factory there apparently is a difference haha. but with the stuff done to my car the sidepipe is prob the least of my problems

[Deleted]

Oct 25, 2013 20:30:56 GMT boostwagon said:

BUT

Vosa has a slightly different approach since they say it has to exit out the back.....then again Vosa says your not allowed to put a cold air intake, decat pipe, race exhaust or any other aftermarket bit on your car either

Not quite true, the exhaust has to be fitted as to not allow any fumes to enter the cabin, there are no rules or regs about fitted cold air intakes as long as they can not cause injury to pedestrians same goes for anything fitted including any aftermarket items, decat pipes are a no, and no rules or regs about race pipes as long as cat and noise levels are still okay and there are not stamped for off road use only.

If VOSA insisted that the pipe had to exit at the rear then that is what the MOT would state as the MOT is the VOSA test.


Here are the five reason for failure in the exhaust section of the MOT manual...
*An exhaust system not adequately supported.

*A major leak of exhaust gases from any part of the system.

*A catalytic converter missing where one was fitted as standard

*A silencer in such condition, or of such a type, that the noise emitted from the vehicle is clearly unreasonably above the level expected from a similar vehicle with a standard silencer in average condition.

*An exhaust pipe positioned so that fumes are likely to enter the driver’s or passenger area.