That’s how Subaru “squeezed” 341 hp of WRX STI S209

That’s how Subaru “squeezed” 341 hp of WRX STI S209

January 20, 2019 0 By autotimesnews

As in the German BMW M4 GTS coupe, the engineers of the Japanese brand used water injection to increase the total power, but it works a little differently.

One of the highlights of this year’s Detroit Auto Show is perhaps the appearance of the WRX STI S209, the first Subaru S Series to hit the US market. According to unofficial data, its powerful engine is 341 hp.

To achieve this figure, many technologies have been applied, in particular, water injection.

A team of engineers decided to explain to us how water helped increase the overall engine power. Please note that although the water injection in the new WRX STI S209 has several similarities to the water injection from Bosche in the BMW M4 GTS, the first one still received many differences.

 First, due to the fact that the engine is located relatively low, Subaru engineers installed an intercooler in its upper part. This shortens the time it takes for the cooled air to reach the engine and helps reduce turbo lag. It also allowed Subaru to take advantage of air cooling through the hood vents.

The driver can independently use the water injection of the intercooler. In cases where the outdoor temperatures are high, water injection helps to further cool the air from the intercooler by 10 degrees Celsius using evaporative cooling. And, as we know, the denser and colder air entering the intake manifold passes more fuel into the combustion chamber and, consequently, increases power.