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Is the downpipe legal?

A common question we get asked is is downpipe installation legal. 

Let's find out in this article

The downpipe is an exhaust component for vehicles that is installed to increase the power and performance of the engine.

If you want to find out exactly what it is, in  THIS ARTICLE  we have talked about it in detail

In some countries around the world, installing a downpipe could be considered illegal or not compliant with road safety standards.

In Italy, for example, it is necessary to check that the downpipe complies with the vehicle approval regulations and that it was installed by a specialist workshop.

Furthermore, it is important to check that the downpipe does not emit noise levels or exhaust gas emissions exceeding the limits permitted by law.

If the downpipe does not meet these conditions, it could be considered "illegal".

the downpipe is legal

Is there really an approved Downpipe?

Apparently the answer to this question is: Yes, there are approved downpipes for some vehicle models.

But let's take a closer look at the matter.

A homologated downpipe is an exhaust component that has been tested and approved by the relevant body to ensure that it meets the safety and emission standards required by law.

Always referring to Italy to name a country, for example, an approved downpipe must be certified by the vehicle approval body (Ministry of Transport) and must be installed by a specialized workshop that issues the installation certificate.

So far so clear, but where is the catch?

Given that the approved downpipes are designed to meet the emission standards required by local legislation.

In Italy, for example, homologated downpipes must meet the car's original Euro standards.

The problem is that a 200-cell downpipe for example (but also 400 cells) comply with Euro 1, Euro 2 or Euro 3 anti-pollution regulations depending on the model of catalyst fitted.

When buying a street legal downpipe it is important to check that it has been tested and approved for road use and that it meets the emission standards set by the original car. 

This in 100% of cases never corresponds to reality.

The "Approved" downpipes are actually approved for Euro 1, 2 or maximum 3 emissions, anyone who claims otherwise is lying.

If you are looking for a 200 cell downpipe just because it is "approved" you should remember that in reality it is not for your car.

There is a homologation, but this does not correspond to the one that your car requires to be homologated.

Consequently, you would only make a further useless extra expense, paying for a product that is NOT approved in any case.

You're basically fitting a euro 1 downpipe on euro 6 cars (to give an example on recent cars).
The Euro 6 standards are newer and more stringent than the Euro 1 standards and set lower exhaust emission limits for motor vehicles.
Therefore, a downpipe approved for Euro 1 standards is not able to meet the emission requirements of the Euro 6 standard.

Think about it for a moment...

Why should the parent company throw money away on difficult projects, limit engine performance, overcome homologation difficulties, if a simple 200 cell downpipe were enough to solve all the problems?!

Because the installation of a 200 cell downpipe can certainly increase engine performance and make the vehicle faster, but however, there are also other considerations to take into account.

Installing a downpipe increases noise and exhaust emissions levels, which would make it non-compliant with local noise and air pollution regulations, even if it is "approved" (pretend then) with a 200 catalyst cells.

This is why car manufacturers invest a lot of time and money in developing engines that meet the latest emission standards and in overcoming homologation difficulties.

No installation of a 200-cell (but also 400-cell) downpipe could be considered legal, otherwise the cars would already come standard with this type of downpipe, as happened on older cars.

So what solution?

Unfortunately the solution does not exist. The only approved downpipe is the original one. We at InoxPower don't lie to you by offering you fake approved Downpipes, making you believe that everything is in order.

You have to put your heart at peace, there is no approved downpipe.

If you have a latest generation BMW, Euro 5/6/7/8/50... and you decide to install a racing downpipe, either you mount the stock model (which is anything but racing) or NO other model is approved for your car, even if someone claims otherwise.

The installation of a racing downpipe is intended only for use on the track or on roads closed to the public. 

But it is also true that it is estimated that an increasing number of people (over 60% of users) empty the DPF (particle filter) or the OPF (for petrol engines) of their vehicles.

Emptying the DPF is not recommended as it still leads to the emission of greater quantities of particulate matter into the air, which also makes it non-compliant with local regulations on air pollution.

Also, removing the DPF could have a negative impact on performance, engine life and long-term reliability. 

The correct solution in these cases is to restore the stock downpipe, replacing it with a new one.

This solution in real life is adopted by a very small number of people. Most opt ​​for an aftermaket downpipe.

In this case, however, remember not to fall into the trap of the approved "fake".

If you have a BMW, the best choice you can make for your car is to install a  DOWNPIPE INOXPOWER