Pros and Cons of Aftermarket Downpipes for the N55

The BMW N55 engine is famous for its smooth power delivery and tuning potential capabilities. Now if you are someone who wants to add more power or improve the exhaust note, then upgrading your downpipe is the way to go. It is the most effective modification you can make to your car to achieve your goals.

However, you may question whether it is worth it. After reading our list of pros and cons of aftermarket downpipes for the N55, we will leave this up to you to decide.

Pros of Aftermarket Downpipes for the N55

Everything has its advantages and disadvantages. Likewise, some of the pros of aftermarket downpipes are:

1. Increased Horsepower and Torque

One of the biggest and most obvious advantages of an aftermarket downpipe is your vehicle’s improved performance. This happens when turbo engines like the N55 can produce more power by reducing exhaust restrictions. Upgrading to high-performance N55 downpipes can significantly improve exhaust flow and boost your BMW’s horsepower.

When there is a reduction in back pressure, it will allow the turbo to work more thoroughly. In doing so, your vehicle will experience more power and smoother power delivery.

2. Faster Turbo Spool

When there is a less restrictive downpipe all the exhaust gases will be able to flow around more freely. This will then lead the turbo to spool up quicker. All of these add to improving the throttle response, which will make your car more responsive.

So, the quicker the spool, the faster the boost pressure will build up. This will, in turn, reduce the turbo lag and improve the overall acceleration.

3. Lower Exhaust Gas Temperatures (EGT)

When there is an improved flow, the exhaust gases will exit your vehicle more efficiently. This will lead to lower exhaust gas temperatures (EGT). All of these will help in boosting the longevity of your engine parts.

Not to mention, lower EGTs will also reduce the strain on your turbo and other exhaust system parts in your car. It will reduce any risk of heat soak or premature wear from taking place.

4. Optimized for Tuning

If you want to tune your N55, then you should definitely consider getting an aftermarket downpipe. In doing so, your engine will be able to utilize the performance software fully. This will make the tunes more effective.

However, the stock exhaust system will limit airflow without an upgraded downpipe. It will in turn prevent you from fully taking advantage of the engine control unit (ECU) modifications. So, with a proper tune, an aftermarket downpipe will lead to a higher peak power and improve the overall throttle response.

Cons of Aftermarket Downpipes for the N55

However, there are also some downsides to aftermarket downpipes for the N55. Some of these are:

1. Check Engine Light (CEL)

When you are removing or altering the catalytic converter, it will trigger the check engine light (CEL) to turn on. So you need to tune your car right after installation. The constant check engine light will always be on display if you don’t. It will also interfere with other diagnostics in case of engine-related problems.

2. Emissions and Legal Concerns

Many places have strict laws regarding emissions. If you have a catless downpipe, your car has a high chance of failing inspection. Even high-flow catted downpipes are not legal in some states and countries. So, you should always check the regulations of where you live before installing a downpipe.

3. Unpleasant Exhaust Odor

In some cases, after installing a catless downpipe, there will be a strong and raw exhaust smell. This is mainly due to unfiltered gases. So, if you are driving your car regularly, this will serve as a huge downside, especially if you are in an enclosed space for a long time.

On the other hand, a high-flow catted downpipe will help in reducing this problem. However, some odor will still be present compared to a stock downpipe.

Choosing the Right Downpipe for Your N55

If you have decided to upgrade to an aftermarket downpipe for your N55, the next step is to find the right downpipe for your needs.

There are catless downpipes that provide the maximum amount of power gains. They lead to better turbo spool as well as increased horsepower. However, they have some downsides, such as a strong exhaust odor and high emissions.

On the other, there are high-flow downpipes that have fewer restrictions as compared to stock. However, they won’t provide your car with as much power as a catless downpipe. If you want the best of both, you should go for a high-flow catted downpipe.

Conclusion

Overall, aftermarket downpipes for the N55 come with a lot of performance benefits. However, it also comes with some disadvantages. So, based on what you want for your car and how you want it, you should decide if you are going to invest in an aftermarket downpipe.