Intercooler Heat Soak: How to Prevent It
Intercooler heat soak is a condition that occurs under high load, high ambient temperatures, or insufficient intercooler size or quality. It causes the intake air temperature to increase.
High intake air temperatures can cause a reduction in power, this is due to reduced oxygen concentration in the intake air, reducing air content in the combustion chamber, reducing the power potential.
Other problems that can occur are a reduction in overall efficiency, and possibly knocking or detonation occurring. Knocking and detonation can cause engine damage.

How to Prevent Intercooler Heat Soak?
Preventing heat soak can be done in various ways, such as the following.
Driving accordingly
Increasing air flow
Fitting a larger intercooler
Using a higher quality intercooler
Installing intercooler water spray
Driving Accordingly
What this means is driving according to the weather and ambient conditions, for example if its raining, windy, or it is colder, there will be less heat soak. If it is hot, dry, and not windy, there will be an increase in heat soak.
You can plan around this, if it's not ideal weather, driving hard may not be a good idea.
Increasing Air Flow
Increasing air flow to the intercooler may be a good idea. You can do this by way of adding vents, moving intercooler placement (such as from a top-mount to a front-mount), or even changing trim to allow air flow (such as open grills).
Fitting a Larger Intercooler
Installing a larger intercooler is one of the most effective ways to prevent heat soak. It has multiple advantages; increases surface area, increases volume, both of these increases the amount of heat removed from the charge air within the intercooler.
Using a Higher Quality Intercooler
Another way is to upgrade to a higher quality intercooler, such as intercoolers with a higher density of offset internal fins, cast flow-optimised end tanks, etc.
Installing Intercooler Water Spray
Intercooler water spray is an effective modification that allows you to spray a mist of water over the intercooler, increasing heat transfer to the ambient air.
This is even able to reduce intake air temperature to ambient temperature, making it highly effective for short-term use.
The Optimal Intercooler
An optimal intercooler for preventing heat soak would have the flowing qualities.
Front-mounted
Bar and plate
Cast and flow-optimised end tanks
High-density internal fins & low-density external fins
Offset-style internal fins & straight louvered-style external fins
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