Exhaust systems, removing the gas
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The exhaust system on your vehicle is an important part of the combustion process in your engine. The intake side mixes fresh air with usually petrol or diesel, feeds it into the combustion chamber in the cylinder head, where it is detonated (controlled explosion) and the exhaust system takes that residue gas flow and expels it out the back of the vehicle. At Repco, we stock exhaust systems and accessories from Redback, Permaseal, Goss and Fuelmiser.
What does an exhaust system do?
Combustion produces noise and exhaust gas which is extremely hot and through a length of exhaust pipe and components, ducts it out the rear of the vehicle. There are a lot of component parts that make up the exhaust system and these can be purchased individually or as a set. Lets run through it from the front where it leaves the exhaust port on the cylinder head to exiting the rear of the vehicle via a chrome exhaust tip.
To start its journey the exhaust gas first passes through the exhaust manifold or if you have a performance exhaust, an exhaust header or extractor system. Performance exhaust systems are less restrictive and create a better exhaust flow to remove exhaust gas more quickly. This creates better engine performance resulting in an increase of engine power.
Catalytic Convertor (Cat)
The next part in the exhaust system we find as we travel down the exhaust pipe is the Catalytic Converter or Cat as it is usually called. This takes toxic gases from diesel and petrol engines and makes them less harmful for the environment. It turns carbon monoxide to carbon dioxide and reduces nitrogen oxides. The catalytic converter is one of the most expensive parts of an exhaust system.
Diesel Particulate Filter (DPF)
A unit you find on diesel exhaust system is a Diesel Particulate Filter or commonly called DPF. This exhaust component is similar to a catalytic converter as it is needed to reduce exhaust emissions. It filters out particulate matter soot from the exhaust.
Exhaust Gas Recirculation (EGR)
Another unit you find on a diesel exhaust system is the Exhaust Gas Recirculation system or commonly called EGR. It is designed to decrease harmful Nitrogen Oxide (NOx) emissons and reduce the likely hood of detonation due to high combustion temperatures. The higher the combustion temperature the more NOx is produced. It cools some exhaust gas (using water) and bleeds the gas back into the intake manifold. This reduces the intake mix and cools the combustion temperature.
Resonator & Muffler
As the exhaust gases go further down the exhaust pipe the next few items in the chain are a resonator and an exhaust muffler. Most engine noise comes from the exhaust system and noise level is greatly reduced by these exhaust components. The engine exhaust creates exhaust pulses which send sound waves down the exhaust pipe and these two items reduce the sound levels to a level that doesn't hurt your ears. They also play a big part in producing an exhaust systems exhaust note.
Exhaust pipes & Tips
These connect all the pieces together and come in all sorts of shapes and sizes to fit around suspension and drive train components under the car. The most common way of fitting them together was one end of the pipe was larger so you could push them into each other and use a clamp to hold them together. As there are so many components in a modern exhaust, flanges with a gasket in between that bolt together are more common now. The tip is about the only thing you see sticking out of the car and is decorative, commonly polished stainless steel or a chrome finish.
Exhaust Hangers, Clamps & GasketsThese are the vital pieces that hold up the exhaust and keep it sealed. The brackets, rubber O rings and clamps hold up the exhaust pipe and stop it hitting the ground or other components under the car. The gaskets join the pieces together and stop the joints leaking exhaust gas.
Why do I need an Exhaust system?
Originally the exhaust system served two purposes and that was to duct the hot, unbreathable gas away from the cars occupants and to quieten down the sound of the engine. In more recent times a third purpose was to filter out harmful pollutants. It is important to keep your exhaust in good condition and fix any leaks or blockages as soon as they occur. Normally these are easy to spot as the exhaust note changes. (usually gets noisier) Even exhaust hangers are important as a loose exhaust banging around under the car will just lead to a more expensive fix it left unchecked.
What is the benefit of a performance exhaust?
Adding a performance exhausts to most vehicles upgrades the power output, generating more horsepower which gives a performance increase that can be dyno tested. Often performance exhaust systems will run two pipes or what is commonly called a dual exhaust system or a larger single exhaust to get performance gains from the engine. The mufflers and resonators are less restrictive and more free flowing to help the gases escape faster. They are slightly noisier and to an enthusiast it gives a great sounding exhaust note. They are usually finished off with bold polished stainless steel or chrome exhaust tips.
Stainless Steel exhaust, why is it better?
A lot of aftermarket exhaust products these days are made from stainless steel as it lasts a lot longer than a standard mild steel exhaust system. Even stock exhausts are using stainless steel products for durability and reliability as stainless steel is harder than mild steel. It is good thing to put on a classic car that is not driven that often. The reason is when the exhaust cools it forms condensation inside the system and this water sits in the exhaust causing corrosion. Cars driven regularly clear this on a regular basis.
Whether you are looking for a stock exhaust system or a performance exhaust system Repco have all your exhaust system needs. From exhaust manifolds, catalytic converters,stainless steel car exhaust systems, cat back exhaust systems to a chambered muffler we have something to suit your model car. Use the rego search function on the Repco website, or talk to one of our staff at your local Repco store today to view our whole range of car Exhaust Systems.