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They came close in Bahrain. Lewis Hamilton or Nico Rosberg might have done it in Canada, but for Mercedes reliability issues. Then, it finally happened last weekend in Belgium—the fastest race lap, set by Rosberg, was quicker than the fastest lap at the 2013 Belgian Grand Prix.

At the beginning of the season, all the talk was about how quiet and efficient the new Formula One power units were. Lost among the lack-of-noise complaints, though, was the fact that the new hybrid V6 engines actually produce more power than their louder V8 predecessors.

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For example, the top speed recorded on the Circuit Gilles-Villeneuve's long straight at the 2014 Canadian Grand Prix was 347.1 kilometres per hour, by Williams' Felipe Massa. In 2013, the two Saubers of Nico Hulkenberg and Esteban Gutierrez led the way through the speed trap at 321.6 kilometres per hour.

But along with the increase in power for 2014 came a decrease in aerodynamic grip, meaning the new cars are not as quick through slow- and medium-speed corners.

In March, after the Australian Grand Prix, I wrote that, "In September, the grand-prix circus returns to Monza, where speed is king and downforce is an afterthought. By then, if not before, it would not be surprising to see lap times similar to—or faster than—last year's."

Mercedes executive director Toto Wolff agreed, saying, "These cars are going to go quicker than the old ones in a couple of races," per Andrew Benson of the BBC.

Here are the race-by-race gaps between the 2013 and 2014 fastest laps. The Austrian Grand Prix is not included, as it was not on the calendar last season (although, in case you are interested, the fastest lap this year was 3.805 seconds off the best time from 2003, the last time the race was run).

Also missing is the German Grand Prix, which was run at Hockenheim this year but the Nurburgring in 2013, making a comparison impossible.

Compiled by the author.

In Bahrain, the third race of the year, Rosberg's fastest lap was only 0.059 seconds slower than the best lap from the 2013 race, set by Red Bull's Sebastian Vettel. The four long, high-speed straights at the Bahrain International Circuit compensated for the cars' slower speeds through the corners.

Four races later, in Canada, I thought one (or both) of the Mercedes cars would be able to top the 2013 fastest lap. But, halfway through the race, they both suffered problems with their energy recovery systems, which slowed the cars and eventually forced Hamilton to retire.

Massa then set the fastest lap, 2.322 seconds slower than the best time from 2013.

David J. Phillip/Associated Press

Before the mechanical gremlins struck the Silver Arrows, though, both drivers were able to record laps that were within half-a-second of Massa's eventual best time—but the Mercedes drivers did it with significantly more fuel onboard (Massa's quickest time came on Lap 58, Rosberg's was on Lap 33 and Hamilton's on Lap 24).

We can't know for certain whether the Mercs would have beaten the fastest 2013 time, but it would have been close.

The next real opportunity for someone to better a 2013 fastest lap came last weekend in Belgium. The Circuit Spa-Francorchamps has a high-speed layout, with 70 percent of the lap taken flat-out, according to F1 Fanatic (compared, for example, with Canada, where 59 percent of the lap is at full throttle).

And while Rosberg did beat the fastest lap from 2013 by 0.245 seconds, he was the only driver who was close.

The next quickest time in the 2014 race, set by Sauber's Adrian Sutil, was 1.902 seconds off Rosberg's pace. Hamilton would likely have had a fastest lap similar to Rosberg's, but he was never able to run at full speed after his team-mate punctured his tyre on the second lap.

While the gap from Mercedes to the rest of the field is still significant, it also demonstrates the potential of the new cars and, specifically, the hybrid power units.

Alessandro Trovati/Associated Press

The 2013 fastest lap will likely be beaten again at the next race, the Italian Grand Prix. After Italy, it is difficult to say whether it will happen again this season.

However, as the teams find more aerodynamic grip within the current regulations, the engines are fine-tuned to produce even more power and the drivers become more comfortable with the new cars, lap times will continue to drop.

Despite those who are still complaining about the lack of engine noise, the cars are faster in a straight line and now, in at least one case, over a full lap.

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