Why Honda is still up against it

Two races down and already McLaren-Honda has a point to show for its efforts in Formula 1 this season. That's a point more than it managed across the first five races of last year. But for Jenson Button's retirement in Bahrain it might have scored more.

The MP4-31 is close to being a regular top-10 contender on pure pace, rather than back-of-the-midfield fodder like last year's MP4-30. Undoubtedly this is a big improvement on 2015.

Given its resources and championship-winning pedigree, McLaren should be producing a chassis capable of running at the front. Thanks to the restructuring completed since racing director Eric Boullier joined the team in late-2013, it seems McLaren is on the right track in that regard.

Not all the way yet, but its two world champion regular drivers are complimentary about the way the MP4-31 handles. The constant development seems to be working.

Honda has also made big strides forward, particularly in regard to its Energy Recovery Systems. The new power unit features a bigger turbine and compressor, and can now recover a much greater degree of energy from the exhaust gases to recycle into the battery.

The result is the drivers have more electrical energy to play with, which means they no longer run out of steam so badly at the end of the straights.

Fernando Alonso stand-in Stoffel Vandoorne genuinely overtook Sergio Perez's Mercedes-engined Force India during the Bahrain Grand Prix. Such a thing would have been unthinkable 12 months ago.

The ERS is working well and McLaren-Honda is a competitive midfield proposition now, rather than a laughing stock. But the aim is to fight Mercedes and Ferrari at the front, so there is still a long way to go. Now the crisis is overcome, Honda faces its real challenge.

Despite all the fancy ERS systems that bulk out the power units in current F1 cars, it's still the good, old-fashioned combustion engine that dominates the competitive equation.

The 100kg total fuel limit for racing, and the maximum 100kg/h fuel-flow rate that accompanies it, means combustive efficiency is the name of the game. The less fuel and oil you can burn for the same resultant energy, the better off you are.

Market leaders Mercedes and Petronas say they reached 45 per cent thermal efficiency at the end of 2015, and feel there is still plenty more to come.

Ferrari and Shell seem close, but were a bit slow on the uptake initially and perhaps haven't got their latest processes working quite so smoothly. Certainly the Ferrari engine looks less driveable off the slow corners than the new Mercedes unit.

When you produce more power it usually comes at the expense of driveability, and that can take time to balance out properly with the correct fuel maps and engine settings.

This is something Renault struggled with badly at the start of last season. The French manufacturer has come a long way since the disastrous scenes of early-2014, but poor reliability returned at the start of '15, after it rushed out a combustion update that was unreliable and difficult to tame on the track.

Renault admits it placed too much initial emphasis on the ERS systems on these power units in 2014, at the expense of combustion development, and has been struggling to make up the ground lost as a result.

It seems Honda has fallen into a similar trap.

The raw appeal of the current regulations to manufacturers like Honda is the opportunity to create innovative hybrid systems and prove their quality in competition.

As outgoing F1 engine chief Yasuhisa Arai told Autosport during Honda's first test in Abu Dhabi in 2014: "How to make a whole sophisticated system is a very big challenge. On the hardware side, the MGU-H is a little bit complicated. High rpm. And the turbo heat."

This is the exact area that caused Honda so much woe in 2015, and its combustion development seems to have naturally suffered as a result of needing to focus on fixing these problems.

Producing effective combustion updates that can work properly in sync with all the other systems is also extraordinarily difficult. Mercedes is the master, Ferrari is catching up, Renault spent most of the last two years scratching its head, and now Honda is doing the same.

Arai admitted last year that Honda underestimated the difficulty of this engine formula, and his successor Yusuke Hasegawa says he was surprised at the level of technology involved purely on the old-fashioned combustion side.

"Before I came to this position I didn't realise that F1 engines were such a very high level of internal combustion engine technology," Hasegawa tells Autosport.

"From an internal combustion engine point we clearly understood our top-end power isn't good enough. It is very important point that it needs to improve, especially for overtaking not very strong cars.

"I don't want to disrespect, but even the Sauber or the Haas they [McLaren] struggle to pass. I think it's coming from the top-end speed, so we need more top end speed. It's very clear."

But achieving this ambition is not a simple fix. Reliability was desperately poor last year. Alonso and Button used 23 combustion engines between them in 2015. OK some of those swaps were tactical, but the rules mandated four per driver for the whole season before penalties applied...

Honda spent 18 of its 32 allocated development tokens to update its engine for 2016, but pure power remains roughly "equivalent" to the end of last season, according to Hasegawa.

The feeling is there is more potential in the current V6 spec, but it cannot be used without potentially introducing new reliability concerns.

"We didn't gain too much," he says. "We got reliability, and the deployment. We will keep pushing to provide the extra power. So far it's almost equivalent as it was last year."

Hasegawa says there has also been a tactical choice made to dampen engine performance slightly, to allow McLaren the reliability needed to focus on extracting the most from its chassis, which may be worth more laptime at particular circuits than extra horsepower.

"We thought just providing maximum power wouldn't make sense," explains Hasegawa. "We have to find a good balancing point from the reliability and the power.

"I don't want to create three-lap engines. To find the balancing point is a particularly important and difficult job. Just getting maximum power is not difficult.

"The Honda manufacturer's point of view is we try to create the best engine. Because the aim is to get a good position as McLaren-Honda, just concentrating on the engine is not good tactics.

"Sometimes just getting 2kW isn't that big a difference for the circuit laptime, but for Honda that's very good. We have to always push our members to insist 2kW.

"But it's important that the team can concentrate in the set-up of the car and the driving. Sometimes that's more important than a 2kW gain."

To add performance to the combustion engine without detonating it to bits has always been the aim in motorsport, but it seems particularly difficult in V6 hybrid turbo F1.

Engine builders for this formula talk about becoming 'the masters of knock', because the unique demands of the fuel-limited formula put enormous pressure on the engines, quite literally.

"Previously the thought was that an engine with more power requires more fuel, but with these regulations more power means fuel consumption is better, so it's interesting," Hasegawa adds.

"Fuel is not the only element, but it is an important element. It has a lot of the factor to control the efficiency and the anti-knock.

"Because of the higher efficiency the higher compression ratio is [also] very important. From a component point of view, the more power we give the cylinder block or a piston or other reciprocated parts, the more stress. So from that point of view it's more difficult."

Now its ERS woes seem firmly behind it, and McLaren-Honda can now race competitively with other cars, even on power-sensitive tracks like Sakhir, the challenge is to master a complex combustion process that is complicated by those recovery systems, and made even more difficult by the high-efficiency demands of the fuel limits.

The mission for Honda and fuel partner Mobil is to work out how to out-develop Mercedes/Petronas, Ferrari/Shell and even Renault/Total, which are all further down this road and show no signs yet of letting up.

Honda has come on leaps and bound since it joined the party, but it seems the real work still lies ahead.