Driving for Meco Motorsport, Raj had qualified fourth on the grid and finished race one in the same position before following it up with a second place in race two.
The weekend had started on a difficult note the team worked to find the right setup to suit the 4.6-kilometre layout.
The venue, which also hosts the F1 Chinese Grand Prix is a unique challenge on the setup front, as sectors 1 and 2 consist of high-speed corners, while sector 3 has long straights - the longest being over 1.1-kilometre long.
"The new tyres and engine package makes it a new car altogether, so we spent a lot of time chasing a good setup in the practice sessions. We knew that low-downforce was the way to go, even though it makes the car slightly more on the limit," he elaborated.
Although Raj was able to muscle his way to the sharp-end of the grid in qualifying, he was unable to get close to pole position - a feat that he had achieved in Zhuhai two weeks back. As a result he had to settle for fourth on the grid but there were other contributing factors as well.