While confident in what they were doing, it wasn't until they demonstrated their speed relative to their rivals that van Gisbergen could see how successful the project has been.
"It was always going to be tough building our new cars, trying to understand the differences," he said. "They look awesome, went well and quite different but it was really, really fast. To match the other guys, who were quick last year, the team has done a great job.
"We just worked hard, we had to do a lot of work. The amount of work at the shop to get the cars going has been pretty outstanding."
After sweeping the weekend van Gisbergen admitted he and the team celebrated in style Sunday night.
"It was awesome – everyone has been pushing so hard for so many months and we have not had time to get together and socialize so to enjoy [the celebrations] was pretty good."
The next round is at the Australian Formula 1 Grand Prix in a fortnight.
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