Cars can be modified in dozens of ways to produce the desired results. Performance tires, for instance, improve handling and grip at higher speeds, and are directly involved in getting engine power down to the ground. Engine upgrades like turbos and forged internals help with overall power and torque. But almost every project begins when swapping out the stock intakes and exhaust system.
These let the engine breathe to significantly increase efficiency, leading to better burns and an increase in available grunt. For anyone interested in modifying their car, an aftermarket car exhaust system is often the first automotive part they consider. These parts provide the basis for faster acceleration, higher top speeds, and an engine sound that turns heads.
What’s Missing in Factory Exhaust?
Factory exhausts are built to a price, and often as a cost-cutting measure to keep overall vehicle prices down. They mainly consist of narrow crush-bent mild steel that slithers in multiple bends to accommodate to the car underbody. While adequate for most uses, their shortcomings become evident when you’re harder on the gas.
The design and subpar build doesn’t do the engine justice, creating excess backpressure or lingering gases within the tubing, and choking the engine of its next breath. It also struggles in wet weather and on poor roads, with increased instances of corrosion and the mild steel is susceptible to higher pressures and temperatures and impact from road imperfections. All this can lead to power loss, decreased engine efficiency or failure to pass an emissions test.
Benefits of Performance Exhaust Parts
The wider, straighter tubing, superior materials and better build all contribute to a range of benefits:
- Increased power and torque – more space allows for better airflow with fewer restrictions. Spent gases exit the car faster, meaning quicker subsequent combustion cycles. This raises stock power and torque numbers by up to 10 per cent, and is something you can definitely feel when working the throttle.
- Faster acceleration, easier overtaking, better throttle response – faster combustion also means a snappier throttle, and the added power translates to real-world results. Vehicles are more responsive, get to a move on quicker, and drivers have more leeway when overtaking.
- Improved durability – stainless steel in an aftermarket car exhaust lends more strength, higher longevity and decreased wear. More so than the mild steel in factory units. The tubing endures higher temperatures that comes with increased power output, more abuse when hitting potholes and road bumps, and won’t rust even when fully inundated in water or mud. Differences in exhaust wall widths also mean the parts are less likely to rupture.
- Reduced fuel use – with higher engine efficiency and cleaner burns, aftermarket exhausts help save some cash when filling up. This is especially true in bumper-to-bumper traffic.
- Lower weight – exotic materials like Inconel or carbon fibre seen in many performance exhaust parts shed considerable weight, roughly 20 pounds in full header and turbo-back systems. Additionally, aluminized steel in mufflers sheds a few pounds, but can rust over the long term, making it a cheaper option.
- Deeper, throatier exhaust sound – the wider and straighter tubing and faster airflow means you can also hear more of the engine. Bends are used only when necessary to speed things up and add a few decibels. Combining different exhaust parts like mufflers or straight tunes in mid-pipes and catalytic converters also brings interesting sound profiles.
- Customization – downpipes, extractors, catalytic converters, mid-pipes, mufflers, resonators, tailpipes and tips can be combined in different configurations and layouts to get what you want from an aftermarket exhaust. When optioned in straight-tubed or free-flowing variants, they help with exhaust velocity and turbo spooling, and reduce pressure and temperatures for extended engine and exhaust longevity.
Choosing The Right Exhaust For Your Car
There are a few things to look out for when upgrading your factory exhaust system. The chosen aftermarket car exhaust needs to be compatible with the engine in terms of layout, cylinder count, the type of fuel it uses and whether it’s turbocharged or naturally aspirated. This means single systems found in four-cylinder engines or dual exhausts often seen in V6 and V8 engines with dual cylinder banks.
Diesel cars and trucks also feature a DPF filter that works in conjunction with the catalytic converter to burn off more toxic gases and improve emissions. Turbocharged cars additionally require revized downpipes to balance backpressure and turbo spooling. All performance types have wider downpipes or extractors to ease exhaust flow, straighter mid-pipes, and varied muffler and resonator combinations depending on how loud or quiet you want the exhaust to be.
Moreover, there’s a wide selection of materials and looks to be had in the tips, the parts that most people can see. Ensure you’re getting parts or an assembled unit in sturdy materials like stainless steel that has undergone advanced production processes like mandrel-bending or treatment such as coating to ensure strength and longevity, Diameters and widths are another factor, with performance variants often going for 2.5 or 3″ throughout the length of the tubing.
Lastly, choose from “complete” systems. Axle-back types have new parts from the rear axle to the tips, including new mufflers and tailpipes. While they add a few horsepower, they’re more about tuning the sound or improving looks. For sheer performance, cat-back and header/turbo-back systems offer substantial power gains, with some estimates exceeding 10 per cent over factor figures when parts are also matched with an equally capable cold air intake.
Regardless of which type you choose, ensure you’re getting a product under warranty, buy from established brands within your budget, and enjoy the benefits.
