Consider yourself warned, as there's a bit of science content coming your way. Fear not, for it comes with the assistance of an A80 Toyota Supra packing a big turbocharger. That's usually a good formula for fun, especially when there's a see-through intercooler mounted front and center.
That's where the science comes in, courtesy of the Warped Perception YouTube channel. The intercooler's job is simple: cool the air before it enters the engine. Why does that matter? Cool air is denser, which means you get more of it into the engine. More air means more fuel, and that leads to more horsepower. On a naturally aspirated engine, intake air temperatures aren't a major issue so an intercooler isn't needed. But compressed air coming from turbochargers is hot – over 200 degrees Fahrenheit (93.3 Celsius) as seen from this Supra.
The process of cooling down that air is also simple: push it through cooling fins as you have on a radiator. For this particular application, hot air from the turbo enters the passenger-side tank of the intercooler and exits the driver side. It's one thing to talk about the process, but this video features an intercooler with clear acrylic tanks, allowing us to see it with our own eyes.
At first glance, watching air move around seems like a rather boring experiment. Even with a smoke machine in the mix, it's just air going in one side and exiting the other, right? With the help of high-speed cameras, we can see that it's not an instantaneous process. The entire passenger-side tank fills with smoke before we see anything on the other side. We also see temperature differences between the tanks, highlighted by adding a bit of water to clean residue off the clear tanks. On the left, the tank dries almost immediately. On the right, it takes a while.
How much of a temperature difference are we talking about? The final run adds two probes into the tanks, and with the boost pressure cranked up to near 20 pounds, the air temperature reaches 204.6 degrees F (95.8 Celsius) entering the intercooler. On the other side, however, it's just 73.6 F (23.1 C). That's a difference of 131 degrees, and for this Toyota, that can certainly have an effect on power.
Unfortunately, the custom clear tanks fail after that pass, but the point is certainly made. Intercoolers are simple but quite effective at chilling air for boosted cars. Thus ends the science experiment.
