Straight Pipe vs Downpipe: Noise Level, Cost, Emission!

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Last Updated on 11 months by Ollie Barker

straight pipe vs downpipe

If a loud turbo is your fave, then knowing the differences between straight pipe vs downpipe is crucial for a better decision. In this blog, you’ll know what these 2 pipes are and how they differ.

Simply stated, straight pipes are louder than downpipes. Straight pipes will require you to replace the exhaust more frequently than your car’s engine, while downpipes are easier on the wallet and for the wrenching. Downpipes will also be easier on fuel consumption because they offer a cleaner ride, while straight pipes are only about the power.

What is a downpipe?

A downpipe is a pipe that transfers exhaust from the exhaust manifold to the turbo. A downpipe can either be made of stainless steel or carbon fiber alloy, but most are made of the latter. A solid design helps to enhance performance because it does not heat up like a free-flowing system.

Every bolt and nut on an exhaust system provides an entrance for heat to escape from the engine, which can cause your car to overheat; thus making it more prone to engine damage when racing.

There are 2 types of downpipe systems: catless and high-flow catted. Both are made up of a downpipe and midpipe combination. The catless system will not feature a catalytic converter, while the high-flow catted system will have an external catalytic converter.

A downpipe’s main purpose is to reduce exhaust gas temperature (EGT) by routing the hot gases away from the turbo.

A downpipe’s lifespan varies depending upon its construction.

What is a straight pipe?

A straight pipe is the same as a stock exhaust but without the catalytic converter and muffler. A practical straight pipe will be much lighter and allow you to feel every bit of your exhaust note’s vibration through your car’s interior. A straight pipe will also add to your car’s performance because it allows you to feel more power through the gearbox, clutch, and driveline.

For straight pipe exhaust pros cons, you can check out this article.

Difference between a straight pipe and a downpipe

Noise level

There are a lot of differences between downpipes and straight pipes, but the main difference is the fact that straight pipes will make your car louder. The reason is that the exhaust travels through a straight pipe and does not have to travel around your catalysts, which are located at the midpipe.

In contrast, downpipes will have to go through the catalysts before entering the turbo, which means that there is more resistance in the path of the exhaust gases. As a result, there will be less noise generated from these gases as they enter your catalysts.

Investment & maintenance cost

Another difference is that straight pipes don’t have to be replaced as often as a downpipe, so you will pay less money on exhaust parts. However, you need to spend more on downpipe at first.

To install a straight pipe exhaust, you are expected to spend from $1000 to 1500. Whereas, you need to spend more on a downpipe system, which can cost between $2000 and $2500.

Car’s emissions

Downpipes also offer a cleaner and more efficient way of breathing for your engine which makes it easier on gas. As it contains catalytic converters, downpipes will work to decrease your car’s emissions.


Finally, if you’re looking for something other than straight pipes, then a downpipe is the way to go. You can find a variety of downpipes from manufacturers all over the world.


Downpipes are the most popular choice for turbo cars because they offer a cleaner engine and improved performance. Straight pipes may be cheaper and louder, but the benefits don’t outweigh their drawbacks. Nonetheless, if you plan on doing extreme racing, it is probably best that you opt for a straight pipe system just so you can feel the turbo’s power on tap.