Why Do I Need A Downpipe?

Not every car enthusiast is a technical genius or a skilled mechanic. Some of us simply like to drive high-performance cars and have them tweaked by others to go even faster. If this sounds like you, there may be some terms you don’t fully understand when people around you are talking about turbos, superchargers, and other performance components. 

One particular type of performance component that is often discussed by car nuts is the downpipe. But what is a downpipe? What does it do, and do you need a new one for your car? For the answers to these questions and more, grab yourself a coffee and carry on reading our guide to car downpipes.

We’ll start with a couple of very simple but important questions.

What is a turbo downpipe?

A downpipe is a pipe that connects the turbo housing in a turbocharged engine to the exhaust system.

Do I need one for my car?

If you own a vehicle with a normally aspirated engine, the answer to this question is an unequivocal no. Downpipes are only found in turbo engines. Normally aspirated engines have headers connecting the exhaust chamber to the rest of the exhaust system.

If you own a turbocharged car, the answer is less straightforward. Your car may or may not benefit from having a new downpipe fitted. It all depends on the car in question, whether its engine has already been modified, your own performance goals and the type of downpipe the manufacturer installed. We will discuss this in more detail below.

What does a downpipe do for turbos?

If you arrived here after entering “what is a downpipe for turbo” into your favourite search engine, hopefully, you have already found the answer to your question above. But you might not know yet what exactly they do and why a new one might be a good investment.

A turbo pushes exhaust gases out faster than a normally aspirated engine. As the part that connects the turbo housing to your exhaust system, the downpipe affects the speed with which the turbo, and therefore your engine, can rid itself of exhaust gases. 

While its primary function is simply to direct the gases through your exhaust system, the design and specification of your downpipe will definitely affect your car's overall performance. A car fitted with a narrow downpipe containing a restrictive catalytic converter, for example, will normally perform considerably worse than one fitted with a wider, less restrictive model.

So, in summary, a downpipe’s main purpose is to facilitate the expulsion of gases from your engine by providing a connection between the turbine housing and the exhaust system.

Do I need a new downpipe for my turbocharged car?

As we have already mentioned, whether or not you need a new downpipe for your turbocharged car will depend on several factors. There are a few common reasons for replacing the downpipe in a turbo engine:

• Racing 
  If you are planning to enter a production model vehicle into competitive races, you will almost certainly want to modify the engine to the full extent allowed under the rules. A wider downpipe without a catalytic converter will offer substantially improved airflow, which can significantly improve your car's performance. If the rules state that catalytic converters must be fitted, there’s no need to worry because you can also find a wide selection of catted downpipes that offer performance improvements over standard issue downpipes.
   
• Turbo modifications
  If you modify your turbo to run at a higher boost pressure, you may find that a larger downpipe with a smoother bore helps you make the most of the extra performance potential. However, unless you are an experienced mechanic, we recommend consulting a professional before choosing a downpipe for such an application. You are, of course, more than welcome to get in touch with us if you would like to speak to one of our experts about your needs.
   
• Condition of existing downpipe
  If the downpipe fitted in your car has deteriorated to the point where it could lead to a vehicle inspection failure, you will need to replace it sooner rather than later. Whether you choose a standard or high-performance model in this situation is up to you; there’s no need to pay more for a high-performance model if you’re already happy with the way your car performs. 
  
  On the other hand, if you are going to have to pay for a brand-new downpipe anyway, it could be worth paying a little extra for one that gives you more power when you most need it.

If any of these reasons apply to you and your vehicle, you will find a wide selection of high-quality downpipes for sale on our website, all of which can be delivered to your home or business premises anywhere in Australia.

More information on downpipes

If you are looking for an even simpler answer to the question, “What is a downpipe?”, you are welcome to contact us now — we’ll be more than happy to explain everything in clear and easy-to-understand terms. We will also be delighted to provide you with any extra information you may need about the downpipes, blow-off valves, wastegates and other performance components we sell.