Speed isn’t everything in testing. Mileage isn't everything either, of course, but it does mean quite a lot.

At this stage of the Formula 1 season, everyone just wants to log laps as they gather precious data and correlate their new cars and power units with what their simulations have been telling them through the winter.

In an era where engine performance is king, this graphic is a stark reminder of who's ruling the roost...

Kilometers per power unit 22-23rd Photo by: Camille De Bastiani - CdeB DESIGN

Even on the opening day, it was impossible to ignore the crushing display of reliability shown by Mercedes. By the end of Monday, Lewis Hamilton had completed 156 laps, compared with the 87 recorded by the next 2016 car, the Red Bull of Daniel Ricciardo.

As you can see below, the story continued on Tuesday, and it was even more impressive as Nico Rosberg ran 172 laps, or an astonishing 800.66kms.

The next highest total, 134, was also achieved by a Mercedes-powered car, namely the Williams of Valtteri Bottas.

Tonight in Spain, Paddy Lowe says he is targeting 180 laps on Wednesday…

Graphic by: Camille De Bastiani - CdeB DESIGN

Solid start

The Brackley-based team had the advantage of having already done a shakedown at Silverstone last week (sorry I mean 'promotional event'), but then Williams and Ferrari had also done some early running at Barcelona, so that wasn't the only reason why the team was able to record so many laps with such apparent ease.

“You shift your expectations and what you're trying to achieve,” said Toto Wolff this week. “When it went so well like last year there is still room for progress.

“Our plan for today was to do lots of laps and lots of mileage, to collect data, and check various systems and correlation, before we head into the next phase, and this is performance, starting tomorrow [Tuesday] and after tomorrow. So the day really went well.

“We had the plan of clocking so many kilometres, and when we discussed it with Lewis and Nico before testing, and Paddy was saying we might be doing seven or eight or nine hundred kilometres a day, it was an ambitious target.

“But we showed that the team is capable of achieving that, and the driver is capable of holding on to it.”

Nico Rosberg, Mercedes AMG F1 W07 Hybrid Photo by: XPB Images

Beating targets

Lowe himself said that everything had gone even better than expected, admitting that Hamilton had done more laps than had been anticipated.

“We did more mileage than we had planned,” said the Merc technical boss. “So that was good, and no issues on the car. So very happy with that.

“It's more mileage than we achieved in any single day in the last two years, testing with the V6. Our best day yet of V6 testing, in mileage terms.

“We keep raising the bar in terms of how well we engineer the car, and how well we test it in advance in its discrete elements to make sure that when we get to the track it all functions as we intended. I think that's a process that's just got better year on year.

“As we see the cars generally in F1 are becoming more reliable year-on-year, and that's a function of better engineering. We'd like to be the ones in the vanguard of that leading the way.”

Valtteri Bottas, Williams FW38 Photo by: XPB Images

Good day for customers too

Even better for Mercedes is that the fact that the 2016-spec power units in the Williams, Force India and Manor have also run without undue drama, and the miles they log are adding to the knowledge base.

As of Tuesday evening the latest Mercedes engine had completed 3846kms, the Ferrari 1936kms, the Renault/TAG Heuer 1294kms, and the Honda 945kms.

“A good day for the power unit, four cars running the latest spec power unit complete with Petronas fuels and lubes and cooling fluids,” said engine chief Andy Cowell on Monday night.

“It's the start of four examples pounding round the track getting as many laps as possible and pushing as hard as possible to unearth issues.

“As Paddy said, we put a lot of effort in at the factory to make sure we are mimicking the race track as best as possible, but there's no substitute for just being at a Grand Prix track and going round and round and just seeing how well we've done our homework through the winter period.”

Sebastian Vettel, Scuderia Ferrari Photo by: XPB Images

Mileage not king

As noted mileage isn't everything, and Ferrari set the fastest time of the day of course, courtesy of Sebastian Vettel.

Nevertheless Mercedes reminded everyone that the Silver Arrows will be hard to beat once more.

“It's not really a battle of mileage,” said Lowe. “We set out a programme that we intend to follow, how exactly Ferrari intend to reach Melbourne in the best state is up to them. They were clearly doing something different today.”

Typically Toto Wolff was cautious when it came to reading too much into how the start of the test panned out, given that different teams have different agendas. He is not underestimating Ferrari's challenge in any way.

“It depends what you expect from your own car,” said Wolff. “They have certainly been very confident in their car, and they will know the numbers.

“James Allison is no fool. They will know what the target is, they know what you to achieve.

“It's more difficult when you're actually the benchmark yourself, in terms of what development level you need to meet, and I still think they are going to be the team to beat or they are going to be our strongest competitor.

“Of course, starting a day like today where we're doing so many laps and collecting so much data is a good start for us, but maybe that wasn't on their programme.”

Nico Rosberg, Mercedes AMG F1 Team Photo by: XPB Images

“An impressive day”

Wolff did at least acknowledge that a marker had been laid down: “If I were to be in their shoes, which I'm not, I would say that was an impressive day for Mercedes.

“But in the end the stopwatch counts, and today was not about the stop watch and about lap time, and not for them either, so I think we have to not interpret too much on that first day I guess.”

Hamilton is back in the car on Wednesday, and he's looking forward to logging some more miles. He admitted that his first day effort had been tough.

“I feel pretty good today, but I am sore,” he said on Tuesday night, having enjoyed 24 hours to recover. “If you drive a Formula 1 car for the first time, it doesn’t matter how much you train, the next day… It’s like doing a workout if you haven’t been to the gym for a couple of months, or something like that.

“Then the next day you have that soreness. It’s exactly the same.

“So I feel my neck a little bit and my lower back. Tomorrow I will be in the car again and we will be doing even more laps. I believe the goal for tomorrow is to hit 180.”

Let’s see where the mileage charts end up on Wednesday, but this is the story so far...