Free Flow Exhaust System

Nov 11, 2019 | Articles

Do Free Flow Exhaust Systems Really Work?

In years gone by, engine tuners used to throw three words at you for extracting more performance from your engine. These were head, cam, and exhaust. Because an engine is basically an air pump, the idea is to get more air into the combustion chamber. This must happen before the inlet valves close. If this can be done, more fuel can be added, and hence, you will have more power. As such, modifications to the cylinder head will entail head porting and gas flowing. A new camshaft will offer longer inlet valve duration and/or lift. In addition, the exhaust system will typically be converted to a free-flow system.  With less back pressure to evacuate the burnt gasses, the free flow system will function more efficiently.

The technical side

In a free-flow exhaust system, the mufflers are removed or converted to “straight-through” units. These offer less resistance to the gasses passing through the exhaust pipe. In theory, the lower resistance will improve engine performance. This performance improvement will especially be noticeable at high engine speeds. However, without the usual muffling effect of a standard exhaust system, the free flow exhaust can also be significantly noisier. Some of them can be unbearably loud. Nevertheless, this is much less of a problem on turbocharged vehicles, because the turbocharger has a muffling effect.

Free flow exhaust systems may have made a difference in the past. You may, however, rethink that in our current day and age. Modern cars’ exhaust systems are no longer merely an afterthought that manufacturers install to transport gasses out the engine. Nowadays, the flow dynamics of your car’s exhaust are meticulously designed. It can be so good that a modification may impact negatively on your car’s performance. With modern technology, we have catalytic converters that form part of the exhaust system to clean the gasses. These can all limit the extent to which you can modify the exhaust system.

Free flow exhausts, turbo-diesel, and the Unichip

It is noteworthy to mention that the free flow exhaust can nowadays bring about some performance gains. This is possible by fitting a free-flow exhaust to some of the modern turbo-diesel designs. However, be careful not to waste your money. Let the experts advise you on the fitment of a free-flow exhaust system to your turbo diesel. Always do some extra reading when it comes to any system in your car. If you want to read more about the benefits – if any – of the free-flow exhaust system, then click here.

So, let us presume that your car stands to gain from the fitment of a free-flow exhaust system. Why not rather opt for intelligent engine optimisation instead? With a Unichip, we can optimise those overly conservative standardised engine ECU settings. The Unichip delivers a finely tuned fuel/air mixture at all engine speeds. The result is an improvement in both performance and economy, without having to modify your engine at all. It makes your car better without changing it. Because it is a piggyback computer, your car is 100% standard once you have removed it. With the Unichip, there is almost always room for vehicle improvement. Become part of the Unichip family and buy your Unichip today. Click here to contact us.




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