The 3S is a 2.0 L (1,998 cc) inline-four engine with an iron block and an alloy head. While based on the 2S engine of very similar displacement, Toyota went through the trouble of changing the long stroke dimensions of the 2S, giving it a 2 mm wider bore and a 4 mm shorter stroke, allowing for the fitment of larger valves and enabling higher power outputs. First introduced in May 1984, the 3S remained in production until 2007.
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