There’s more to a performance exhaust than just sound and looks. With the Fast Car performance exhaust guide, we will show you why. This guide is jam-packed with the best tips and tricks.
Why would you need a performance exhaust? Almost all standard exhaust systems, we would say almost all, are restricted to some extent even on a standard car, and they are extremely restrictive on a tuned engine.
You can also Google it and can learn more, for example, VW Golf R exhaust upgrade, the results will show you some guidance.
What to consider while choosing a performance exhaust system?
Contrary to popular belief, big power and big noise do not go together. If you had the money and space you could easily build a 1000bhp exhaust system that passed every track day noise limit in the world.
Most performance exhausts are loud because it’s cheaper, easier, and lighter to make a loud exhaust, since it requires little, if any, silencers, not to mention the sound is often an attraction for potential buyers.
As long as the silencer is a straight-through version, the exhaust gases can pass almost entirely unrestricted through the silencer, despite making the exhaust volume much lower.
To build a quiet exhaust, one must first consider the cost. Even though a straight three-inch piece of the pipe may cost $25, a three-inch silencer for the same length may cost $150. And when you think you’ll need four silencers to pass noise regulations, plus the extra pipework and labour costs, it’s easy to see why many car performance exhausts are loud; if they weren’t, many couldn’t afford them!
How to select the best performance exhaust system?
Here are some of the most popular tips you should keep in mind while choosing a performance exhaust system:
Check exhaust silencers
You’ve probably realized that silencing performance with a restriction isn’t a good idea. If performance is important to you, you’ll need to do something else. Extra silencers are the most obvious and effective solution, resulting in no loss of performance. Any competent welder or exhaust specialist can weld an extra silencer or two into your current exhaust system.
People who don’t want to go this far and don’t mind their cars looking a bit odd have their cars fitted with removable extra silencers for track days. To maintain performance, a real silencer costs much more than simply creating a blockage.
Check Exhaust bypass valves
A bypass valve is a standard feature of many supercars and is becoming more popular as an aftermarket tuning option. It can bypass your restrictive but rather quiet exhaust, either with the flick of a switch or at a certain boost pressure, letting the gas out of a less restrictive but somewhat louder exhaust, which is usually a straight pipe. It is important to note that this method keeps static and slow speed volumes to a minimum, but it won’t prevent you from getting black-flagged for excessive drive-by noise.
Check Flapper valves
The flapper valve, which can be controlled electronically or mechanically, works similarly to bungs. By closing them, they restrict the exhaust system and drastically reduce exhaust volume.
Closed, these are even more restrictive than bungs, and we have seen turbocharged cars that are unable to reach even half their desired boost pressure when fitted with one.
Check Performance exhaust flames
Flames can be seen emitted from the exhaust of a tuned car from time to time, and the frequency of these events depends on the exhaust system. Normally if you removed the entire exhaust from a car and revved it while looking at the exhaust ports, you would see flames coming from them when the engine is revved. However, the exhaust length and silencers make these flames invisible at the exhaust tailpipe.
Check Screamer pipes
The majority of people have likely heard of the term screamer pipe, which is a separate exhaust pipe from the wastegate of a turbo car. There is a reason why this pipe is called a screamer since it is normally extremely loud and unsilencing. Because a wastegate does not open until full boost, a screamer pipe won’t cause any issues when driving normally or during MOT procedure, but the noise is almost certain to get you black flagged.
