The Meco Racing driver finished second in Race one behind Chittesh Mandody and third in Race 2 behind winner Mandody and Arjun Maini. Vishnu ended with 179 points and earned himself a free test in European Formula 3 in Italy with Eurointernational.
It was a hat-trick of wins for Mandody, who had recorded his first win yesterday at Buddh International Ciruit.
JK Tyre had introduced this series this year exclusively for India's Under-20 drivers with the technical expertise of renowned racing team Eurointernational, winner of several Formula championships globally.
Vishnu was overall second in drivers championship while Kartik was third.
Rahil Noorani of Mumbai took the top honours in the Volkswagen Polo R Cup even as Gaurav Mehta won the first race of the day, with Jeffrey Kruger and Rahil Noorani in second and third places respectively.
