Honda's success spread beyond Tarquini, enjoying a one-two in Saturday's opener with Zengo driver Norbert Michelisz placing second.
There was almost a clean sweep of the top three for Honda, but Citroen's Sebastien Loeb managed to head the second factory Honda of Tiago Monteiro for third.
Loeb would repeat the trick of denying Honda dominance by beating Monteiro again in the following session, placing second ahead of the Portuguese driver and Michelisz.
The Frenchman was the best of the Citroens throughout the practices with Yvan Muller the next best Citroen in fifth after the first session, before Ma Qing Hua was second to Loeb within the team in sixth later on.
Championship leader Jose Maria Lopez was on the outskirts of the top 10, taking eighth and 10th.
None of the Chevrolets got into the top 10 in practice one, but they improved in the second session, with Tom Coronel impressing to take fifth, some way ahead of Hugo Valente and Tom Chilton in eighth and ninth.
Nicky Catsburg had the best running from the Lada trio with a seventh and 10th, but Rob Huff's ninth was followed by a mechanical problem in the second that meant he finished a lowly 17th.
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