If you’re in the market for a performance upgrade, chances are you’ve had a long, hard look at exhausts. Performance variants bring a host of benefits over what you already have in the car. There’s better airflow, reduced temperatures, piping that can last in different conditions, and the chance to tune the sound. Your car gets to add a few more horses, there’s more feedback from the acceleration pedal, and undoubtedly, a vehicle that’s more fun to drive.
Why Go with a Performance Exhaust System?
All manufacturers cut corners to bring prices down, and the exhaust is no different. In stock variants, this is often made of subpar materials, usually mild steel, and mass-produced using inferior crush bending techniques to save on production costs and time. There are also regulations to be met, meaning the need for lower emissions. The end result is an exhaust that doesn’t do justice to the unused power of the engine.
Tubing is narrower and thinner and impacts how hot exhaust gases exit the vehicle. Moreover, there are more restrictions with multiple bends. All this stifles the performance of any engine, especially in terms of efficiency, and the ability the engine has to draw new air in for another combustion cycle.
Wider Tubing
An aftermarket exhaust solves most if not all of the issues above. First, an efficient performance exhaust is wider, generally half an inch or more in diameter, and this along with the straighter layout allows for gases to escape faster. This is exhaust velocity, and the higher it is, the better. Along with wider piping throughout, exhaust walls are also much thicker, at 1.6mm or more, than what you’d find in stock units. Both factors help with performance and longevity.
Better Materials
Next, is the choice of materials and how they’re processed. High-grade stainless steel is the entry point into performance exhausts, having considerably more tensile strength to endure higher temperatures and pressures. This is a must-have for off-roading, or driving in wet weather, with less likelihood of damage from impact or corrosion. In addition, pipes and parts are formed using mandrel bending, so they’ll hold their own no matter what they’re faced with.
High-end variants justify their price with exotic materials like titanium, carbon fibre, or Inconel that up the bar further in terms of strength, durability, and performance. And they’re materials that are much lighter and improve your car’s looks.
Layouts and Parts Options
Drivers don’t have to spend a fortune to get better performance from the cars. A stainless steel axle-back exhaust proves this, being the least expensive ‘complete’ option. It consists of new piping and parts from the rear axle to the tips, and often with revised mufflers and resonators for better sound, as well as better-looking and more durable tips. Go with resonated options in older cars or when you’re worried about emissions and the exhaust being too loud. Or chose non-resonated systems, often with straight mufflers for something louder and with a bit more presence. Tips can be had in different materials, colours and finishes to round out the look you’re going for.
Cat-back and DPF-back configurations have wider mid-section tubing from the catalytic converter or particle filter to the muffler assembly. The more real estate here increases exhaust velocity and adds some depth to the exhaust note. A nice by-product is an increase in horsepower and torque, in mid to high revs, so more push from the engine at higher speeds.
The last complete option is a header or turbo-back design, depending if the car relies on forced induction. These swap out the old exhaust parts entirely with new piping from the exhaust manifold to the tips. Additional parts, like extractors, wider downpipes and collectors, and solutions that get rid of restrictions (high-flow cats, straight pipes, or catalytic deletes) further help exhaust gases on their way. And the wider tubing along the whole length adds the most power gains and the most decibels. Go with a header or turbo-back if you’re looking for the best performance and deeper, throatier sound.
Choosing What’s Right for You
To get what you need, consider which exhaust configuration best suits your car and what you’re trying to achieve. Axle-back systems shed some weight, get you a louder and meatier sound, and more options in the exhaust tips. They’re also the cheapest, especially systems with aluminised mufflers.
Cat-back and DPF-back systems should be considered by anyone looking for tangible power gains, and something you can actually feel (and hear) with the foot down. Have in mind that some parts (cat-deletes and straight pipes) may not be street legal due to emissions regulations, but well worth the cost if you’re looking for more performance on the track or off-road.
Lastly, if you’re all about the most you can extract from the engine, then header or turbo-back systems are what to look at. They feature revised manifold and header designs to draw spent gases faster, reworked mid-section piping, plus all the goodies of the cat and axle-back variants. They’re much lighter too, with a full exhaust shedding close to 20 kilos over stock. Full systems also serve as the basis for serious mods down the road. A good idea, if you’re going this route, is to also get aftermarket gauges to monitor exhaust temperatures.
What to Consider When Buying
Before splitting with your hard-earned cash, consider vehicle compatibility, fitment, brands, and pricing. Compatibility refers to the engine layout and power output (differences between single and twin systems), the presence of turbines (header vs turbo-back), and the number of cylinders. Manufacturers take out the guesswork, so there should be no problems here.
Fitment means that the performance exhaust you’re set on doesn’t require additional modifications to the car to fit. Shapes, sizes, and how piping and parts are attached to the rest of the car should be all thought out and everything should go nicely in the recesses reserved for the stock exhaust. Considering they are modular and bolt-on systems, this will also be done relatively quickly. Also, avoid brands and manufacturers that don’t supply all the mounting hardware, such as brackets and flanges.
Lastly, go with respected brands. These will have quite a bit of experience (some with racing affiliations) and an extensive range of exhaust lines to suit different vehicles. While the bigger international names do charge a premium for what they offer, you can also choose local brands and save some cash without forgoing quality.