What IS the law re a centre de-cat?
Discussion
Mine is done but of course passes the MOT and emissions test with flying colours as the 4 primary cats remain. It sounds so magnificent and I finally actually got round to doing a professional stereo recording of it with proper pro mic's - but then thought I would check here before I share the music? Insurer is cool with it but anyone any info on legality/new rules etc?
I think that cat's should be as per the factory for the MOT , but that means the inspector needs to know what was originally fitted.
Practically , I imagine that if it passes the emission test , they won't care .
Mine has no secondary cats and no issues on the MOT record ( not mot'd it myself yet )
I also imagine that Aston dealers would not offer removal if it would cause mot issues .
Practically , I imagine that if it passes the emission test , they won't care .
Mine has no secondary cats and no issues on the MOT record ( not mot'd it myself yet )
I also imagine that Aston dealers would not offer removal if it would cause mot issues .
phumy said:
Actually reading that , it is clear that if it passes the MOT , no problem ds666 said:
phumy said:
Actually reading that , it is clear that if it passes the MOT , no problem A couple of points:
- on a V12VS which has been de-catted it is only the same in emissions terms as the AMR version which comes like that out of the factory plus, as someone mentioned earlier, the MOT tester has now idea what the original spec was when it left the factory. I had my Flugplatz car de-catted a couple of years ago and it has come through two MOT’s at different centres without any issues.
- on the noise front I asked when I got my AMR how they got through the noise tests to homolgate the cars. Apparently the test changed before they launched the Vanquish S and some bright spark at Gaydon worked out that the V12, because of its torque, could get through the test in 6th gear and easily met the new noise regulations. I have no idea if this is just a good story but it would explain why they were able to offer the last editions they did on the V12
I was told it wasn’t possible on the V8 because it had to do the test in a lower gear and wouldn’t pass 
- on a V12VS which has been de-catted it is only the same in emissions terms as the AMR version which comes like that out of the factory plus, as someone mentioned earlier, the MOT tester has now idea what the original spec was when it left the factory. I had my Flugplatz car de-catted a couple of years ago and it has come through two MOT’s at different centres without any issues.
- on the noise front I asked when I got my AMR how they got through the noise tests to homolgate the cars. Apparently the test changed before they launched the Vanquish S and some bright spark at Gaydon worked out that the V12, because of its torque, could get through the test in 6th gear and easily met the new noise regulations. I have no idea if this is just a good story but it would explain why they were able to offer the last editions they did on the V12
I was told it wasn’t possible on the V8 because it had to do the test in a lower gear and wouldn’t pass soofsayer said:
Noise levels are discretionary by the tester, so it’s unlikely to cause a problem unless ears start bleeding.
My car has primary cats removed and passed MOTs no issue.
Yes but you HAVE cats mate?My car has primary cats removed and passed MOTs no issue.
I think this may all still be subject to the good old British bobby common sense test - increasingly likely to be jobsworth'd out of discretionary existence to justify someone's final salary pension no doubt (sorry bit tetchy today
). So, if you are blatting about McDonalds in Milton Keynes with super loud farty 4 pot 5" big bore over-fueling for pops and bangs you may get a vehicle defect notice. If you are creating music in the Highlands and have your flaps closed in the village you are upsetting no one. Common sense as I said 
If it goes through the emissions test, thats all that is required, you can do what you like to the cats, including installing free flow ones and as long as the emissions are within limits, thats fine.
At the moment, noise levels are being left to common sense, but there are noise registering "cameras" in planning, although the acceptable limits are quite high.
At the moment, noise levels are being left to common sense, but there are noise registering "cameras" in planning, although the acceptable limits are quite high.
No, there is no noise test done at an MOT. However, the possession of a valid MOT does not automatically mean the car is legal to use on the road. It just means the car has passed the checks which form part of the MOT.
But, the MOT tester does have the power to issue a Fail Notice if he/she considers the exhaust noise to be excessive or unreasonable. No testing equipment is used, it's all down to what the tester deems reasonable and that's consistent with other aspects of the MOT test.
Perversely, although it is not illegal to sell or fit components or equipment which allows an exhaust to be louder than manufacturer's standard at Type Approval, it is illegal to use these items on the road.
But to reiterate, any exhaust which has been modified to be louder than standard is illegal. Illegal and reasonable are not always the same.
(The same regulations apply to emissions, but MOT emissions are not tested at the same level as Type Approval emissions.)
But, the MOT tester does have the power to issue a Fail Notice if he/she considers the exhaust noise to be excessive or unreasonable. No testing equipment is used, it's all down to what the tester deems reasonable and that's consistent with other aspects of the MOT test.
Perversely, although it is not illegal to sell or fit components or equipment which allows an exhaust to be louder than manufacturer's standard at Type Approval, it is illegal to use these items on the road.
But to reiterate, any exhaust which has been modified to be louder than standard is illegal. Illegal and reasonable are not always the same.
(The same regulations apply to emissions, but MOT emissions are not tested at the same level as Type Approval emissions.)
Cold said:
Perversely, although it is not illegal to sell or fit components or equipment which allows an exhaust to be louder than manufacturer's standard at Type Approval, it is illegal to use these items on the road.
But to reiterate, any exhaust which has been modified to be louder than standard is illegal. Illegal and reasonable are not always the same.
Could you please point us to the exact legislation which defines this illegality in terms of noise????But to reiterate, any exhaust which has been modified to be louder than standard is illegal. Illegal and reasonable are not always the same.
Edited by LordBretSinclair on Wednesday 22 April 10:43
LordBretSinclair said:
Could you please point us to the exact legislation which defines this illegality in terms of noise????
It's all part of the Construction and Use regs which implements the EU directive on Type Approval. No I'm not going to dig out the exact paragraph for you because I just cannot be arsed and I'm sure you can find it on the appropriate dot gov page. But there's no need to take aim at the messenger. In a nutshell, you can't modify the exhaust of your car (or motorbike) to produce a more noisy or more smelly result without it being illegal. This is not a statement based on any preachy or moral objections by me. I don't care what you or others on here do to their cars. I don't care what nonsense any MOT inspector or power tripping police officer may get up to either.
It's just a condensed version of what is laid out. A question was asked by the OP and I have answered it. Not my fault if some don't like the answer.
LordBretSinclair said:
Could you please point us to the exact legislation which defines this illegality in terms of noise????
Here you go - UK at leastModified exhaust systems
It’s illegal to modify the exhaust system to make a vehicle noisier after it has been ‘type approved’ (checked it meets environmental and safety standards).
The police can also take action if your vehicle’s silencer doesn’t work in the way it was designed or if you’re driving in a way that creates too much noise.
Source - https://www.gov.uk/noise-pollution-road-train-plan...
The chances of being caught are slim but Cold is quite correct - any more than the type approved levels and the car is technically illegal. I'm sure there is actual legislation that the information and summary in the government website is based on.
Gassing Station | Aston Martin | Top of Page | What's New | My Stuff