Arjun Narendran, the Coimbatore-based defending champion in the Indian Touring Cars category, also completed a double.
With the fifth and concluding round to be run on September 16-17, Reddy, who leads Chennai's Sandeep Kumar by 29 points, is well placed in the championship whose winner earns a ticket to the Mazda Road To Indy shootout in the United States later this year.
It was smooth sailing for Reddy in both the races as he put in a flawless performance to destroy the opposition as he more than made up for a disappointing outing on Saturday when he finished fifth after being forced to pit early in the race for repairs on the nose cone.
Narendran won both races virtually unchallenged, after the initial jostling for track positions.
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Mikhail Merchant from Mumbai (Team Game Over) also scored a double in the Indian Junior Touring Cars category as did Bengaluru's Varun Anekar (Race Concepts) in the Super Stock class.
In the Esteem Cup, Mumbai's Anant Pithawalla (Team N1) consolidated his position at the top of the leaderboard with three podium finishes on the weekend while Mamallapuram's Raghul Rangasamy, who won two races in the triple-header, completed a fine double.