Paddy Lowe, the technical chief of Mercedes which has dominated the early stages of the season, was surprised by criticism of the changes.
"I don't understand it because there are so many positives around this formula," Lowe said. "For an engine to deliver similar power to last year, with more than 30 percent less fuel consumption, is just an incredible achievement and it's something we should celebrate
"Our fans like that richness in the sport. So I hope they also appreciate what's been done on the cars and its sort of relevance to the future in the automotive industry generally."
Bob Fernley, the deputy chief of Force India, said the efforts to make the engines more relevant to road-car production have already borne fruit.
"Honda are coming in next year and it's the first time we've had another major motor manufacturer coming back into Formula One for a long, long time, so that's a tick in the box that says that actually Formula One has got it right," Fernley said.
"We're going to find that the fans are going to embrace this as we go on in the years to come."