Mopar Muscle Association UK

There is a decibel limit as regards exhausts, MOT stations have no means of checking this so it will be down to the tester. You can certainly get nicked for it though, and the traffic police do have the means to check it! From memory the limit is 90db from a given distance from the car. Those Moroso mufflers will be way too loud, I don't even need to hear 'em! Flowmaster 2 chamber mufflers would probably fail as well....

hmmmmmmmm, i think you may be right regards the mot tester, but how many police cars actually carry the equipment required to test ? from what i remember, the test has to be carried out at a certain distance, with no sound reflective surfaces (ie buildings etc) within x amount, a figure of 1/8th mile rings a bell, where, i wonder, will they get me to do that !

many of the ccse guys build their own, Ian Hook built his own ally mufflers but has a rear exit system to avoid the oil/water under the slicks type prob that occurs when a head gasket goes, trouble is, pipecraft only go up to 2 1/2" pipe, and they want it for a whole day due to the ladder bars and stuff, i want 3" to keep it less restrictive, its not a street motor after all !! i dont have a huge amount of space tween the headers and the wheels, nor under floor space as the car sits very low, so big silencers are a problem,

so, where to go and what to do !!


has anyone used those 'supertrap' muffler things ?????
(plates that fix to the end of the pipes and literally stifle noise)

Ive only just spotted this thread and it is a goodie. The MOT bit is interesting, when I MOT'd the Aussie Charger, it had a single silencer side exit exhaust and is very loud. The tester said that he has never tested or seen a vehicle similar to this so he cannot say it is too loud for this type.
He did go on to say that a hot rod is meant to sound loud!!

There is to my knowledge no actual noise limit, for the police purposes of giving a ticket the offences are excess noise and is very subjective , IE in the opinion of the officer. This also covers the loud stereos issue.
The construction and use regulations are also fairly simple, the only thing that seems definite is that internal combustion engines require a silencer.
No specs on how big etc, just needs one fitted.

It would be better if there was a set limit, of say 100dB as they do at race circuits. No dispute then.

As far as I know police cars dont carry noise meters, that is usually the environmental health people that provide the equipment and staff to operate it.

Out of interest does a Turbo count as a silencer? Several guys in the US run straight pipes on Turbo cars on the street, and say that the amount of noise is less than a big block on Flowmasters ...

Yes turbos do make it quieter. you can run a turbo car's engine with no exhaust system whateoever. ok its not quiet, of course, but its definately quieter than a non turbo .

me and a mate recently knocked together a real budget rice rocket (for him) a couple of weeks ago , using a '79 Datsun sunny (RWD) shell and a Nissan Silvia 1.8 injection turbo motor and trans. He used the silvia front box (which is the type you can see right through, as in , like cherrybombs are) and the rest just straight 2" tube, and its not that loud, and passed mot no probs.

we want to run that up the strip sometime. he bougt the engine off ebay for a tenner ! i bet it runs 14's without even tweaking it up

Sounds fun ... the exhaust on the Shelby has a single straight-through silencer and is fine, apart from a resonant frequency at about 1750rpm.

Will , I might want that eng/box combo for my Triumph Herald, it may have a bit more poke than the Toyota Twin Cam lump fitted at present. Bear me in mind if one comes up, what power are they ??
The Toyota is 118bhp approx with a 5 speed box.

coming from you, Matt, that pleases me to read ! thanks :-)