Turbos and temperature – summer weather and turbocharger performance

One common question that we often get from customers is why turbochargers perform differently depending on the time of year, temperature and weather. Generally, these customers have noticed a significant drop in performance on hot summer days when compared to cooler spring and autumn nights.

Whilst this is a common trait amongst all turbocharged vehicles, and isn’t anything to worry too much about – in this post, we take a look at why turbochargers produce less power in hot weather, and what you can do about it.

How turbochargers work

Before we explain why turbochargers perform better at lower air temperatures, it’s important to understand how a turbocharger works.

Essentially, the aim of a turbocharger is to increase the density of the air inside each cylinder of the engine. By compressing the air, more oxygen enters each cylinder, and proportionally more fuel can also enter each cylinder, meaning that more power is generated with each explosion inside the cylinders.

Further info about how turbochargers work can be found on our turbocharging beginners FAQ.

Temperature and air density

As air temperature increases, the density of the air, and the amount of oxygen it holds decreases. This means that the turbocharger has to work harder, spin faster and compress more air to produce the same amount of boost it would at lower temperatures.

As the temperatures inside the turbocharger gets higher, the turbocharger can no longer increase it’s speed efficiently, meaning that knock on effect of this is that engine performance, acceleration and top speed are also reduced.

In addition, hotter air also has a secondary affect on the turbocharger, by naturally increasing the operating temperature inside the turbo. Usually, the intercooler works to cool the air from the hot air intake, but in warmer temperatures, the intercooler becomes less efficient, as it is also exposed to the warmer temperatures.

Again, this serves to increase the amount of work the turbo has to do, reducing the overall efficiency and performance of your vehicle’s engine.

Steps to combat warm weather performance drops

For most people, the drop in turbocharger performance during hot weather won’t be a problem. On most modern turbocharged vehicles, the drop in performance is relatively insignificant, thanks to improvements in air intake, intercooler and air filtration technology.

However, on performance, enthusiast and race vehicles, there are a few steps you can take to improve hot weather performance:

  • Fit a larger turbocharger – as it will provide better airflow under all temperatures and conditions.
  • Replace your intercooler with a more efficient model – reducing charged air temperatures and improving overall performance
  • Fit a cold air intake to your engine – meaning that colder, denser air is brought into the turbocharger
  • Fit a larger air intake – increasing the amount of air available to your turbo
  • Replace your air filter – to ensure that it is clean and free flowing
  • Fit a water or methanol injection system – which can be used to cool either the intake air, or the charged air.
  • Use premium, higher octane fuels during the summer months to compensate for the drop in performance

How we can help

We have a motorsport division and can help with any of the performance suggestions we’ve mentioned above, to increase the power output from your engine. For advice on any aspect of turbocharging, as well as high quality repairs and replacements, get in touch with a member of our team today on 01924894171, or email info@aet-turbos.co.uk