Altitude influence

Does altitude influence engine performance at all? Let us think about this for a moment. An internal combustion engine’s power output depends on the amount of air that it can suck into its combustion chambers. The more air it can get, the more fuel can be added and more power will then be produced. Naturally aspirated engines depend on atmospheric pressure to fill the cylinder once the inlet valves open. Manufacturers optimise cylinder head gas flow characteristics, valve openings, and exhaust system performance. They do this to get as much air into the engine as possible. However, if less air is available, less power will be produced.

This is why all naturally aspirated engines perform worse at higher altitudes than at sea level. Altitude, therefore, does affect power performance. If you want to read more about how engine performance depends on climate and altitude, then click here.

The air and turbochargers

At a typical barometric pressure of 860 millibars, there is nearly 18% less air available. Consequently, with 18% less oxygen and fuel, you can expect an 18% decrease in your car’s power delivery. Did you notice that the old family car is perkier down at the coast than it is up in the mountains? However, you may also come to notice that modern cars seem far less affected than older cars. Is it your imagination, or is there something to it?

Engines want as much air as possible, but it seems to be at the mercy of atmospheric pressure. It is precisely because of this why turbocharging is so popular. A turbocharger is an additional air pump that is driven by the engine’s exhaust gasses. It forces extra air into the combustion chambers. Normal mechanism at differential atmospheric pressure can never achieve what a turbocharger can. Altitude is therefore not much of a concern to turbochargers. What is more, is that a turbocharger can also spin faster to compensate for lower atmospheric pressure. This is why turbocharged cars retain nearly all their power, even at Gauteng altitudes.

Add a Unichip

Of course, it is also more difficult to effectively modify these high-tech forced-induction engines without the help of experts. I, therefore, recommend optimising your turbocharged engine, instead of modifying it. Our Unichip piggyback computer is simply added to the engine’s ECU to optimise its settings. During this process, it will always offer the ideal air/fuel mixture. Not only for maximum performance at full boost but also for maximum economy at part-throttle driving. The Unichip remains the safest non-invasive way to get the best out of your turbocharged engine. Practice responsible car care. Become part of the Unichip family and buy your Unichip today. Click here to contact us.