F1 Frontline - Mark Hughes

As Renault and Honda square up to each other in the battle of the engines, it's the Japanese firm that appears to have the upper hand

It could hardly have been more embarrassing for McLaren in Bahrain when with Renault power it qualified 13th and 14th as Pierre Gasly in the Toro Rosso-Honda qualified sixth. In just his seventh grand prix, the young Frenchman had qualified his STR13-Honda almost 0.6sec faster than the mighty Fernando Alonso’s McLaren-Renault. He was best of the rest after the big three of Ferrari, Mercedes and Red Bull and went on to finish a resounding fourth in the race, Honda’s best result since returning in 2015. Amusingly, on the slow-down lap, Gasly repeated Alonso’s radio message from Australia of, “Now we can fight.”

McLaren, having paid to exit the Honda contract as well as surrendering the income the Japanese company was providing, was now running a Renault-powered car that seemed to show remarkably similar traits to its Honda-powered predecessor. After a winter of unreliability through insufficient cooling the McLaren at Bahrain was by far the slowest car through the speed trap – just as it used to be when it had a Honda in the back. Furthermore, the speed gain when DRS was used was significantly more than anyone else was finding, suggesting that more drag was being dumped. Which in turn suggested that at least some of what Honda used to get blamed for at McLaren was probably rooted in the drag of the McLaren. Which would also have been a factor in the poor economy – and in Bahrain Alonso allowed himself to be lapped at the end so as to save a lap’s worth of fuel while Gasly was adamant that fuel consumption had barely been a concern.

It was a slightly unfair freeze-frame comparison in that the McLaren was much more competitive than the Toro Rosso in the preceding race at Melbourne and the subsequent one in China. But the progress in both the speed and reliability of the Honda power unit this year is very real – and the working relationship with Red Bull’s junior team is vastly better and more open than ever it was with McLaren.

Throughout Honda’s three-year return with McLaren, it always seemed the junior partner. It wanted to enter in 2016 after a further year of development but McLaren insisted otherwise. It would have preferred to have given itself more space in the first year with an all-new, very complex engine technology, but McLaren insisted it must be ‘size zero’ to maximise aerodynamic performance. It was as if Honda was expected to get straight up to the speed in every aspect, which was an unreasonable expectation.

To minimise the external dimensions the original engine featured the turbine and compressor between the vee of the engine. As electrical efficiencies of the new era of turbo electric hybrids improved, so such a layout was revealed as obsolete. The greater those efficiencies, the bigger a turbine that could be justified. Mercedes led the way and into year two of its programme was already using turbines that could never have been squeezed between the vee. Until Honda abandoned that architecture it was never going to be able to run turbos big enough to give competitive power. 

So, the basic architecture of the engine was fundamentally changed and the 2017 engine featured a Mercedes-type layout, with the turbine outside the vee at the back, split from the compressor at the front of the engine. That’s when the big gains were expected – and hence the massive disappointment when the motor proved disastrously unreliable and under-powered. Partly it was to do with a vibration issue that prevented the turbo and MGU-H from running at its design speed – a problem that Honda felt could have been alleviated had there been a little more space available within the installation. But the faith had been lost by this time.

What has been in the back of the Toro Rosso so far this year is a modified version of that 2017 engine with a further upgrade made to the MGU-H after the first race. In race trim its peak power is 12bhp down on the Renault (that’s still over 40bhp adrift of Mercedes and Ferrari). An all-new engine under development (with different heads and block) is due to arrive in Montréal for which an extra 20kW (27bhp) is promised.

What we don’t yet know is whether Honda’s reluctance to use the MGU-H as a relay from the ERS-K to the battery (where there is no regulation limit) has been abandoned. Although the MGU-H can recapture exhaust gas energy, the other engine makers have found more from prioritising it as an electrical relay between the ERS-K (capturing kinetic energy from braking) and the battery. Honda did not follow this practice initially – which could be because its electrical efficiencies were poor (i e it lost too much energy in transferring) or because there was some limitation caused by the mechanical design of the K.

This typically would be revealed by the Honda running out of electrical deployment early on the straights. That aspect seems to have been improved – even in Shanghai, where the Toro Rosso was not particularly competitive, it was second only to the Mercedes in terminal speed at the end of the 1km back straight. Slowest was McLaren. That could partly be a function of lack of downforce – and therefore drag – on the part of the Toro Rosso. But even a low-drag car would need the extra electrical deployment (around 160bhp) not to cut out early if it was to reach such terminal velocities. At the time of writing we were about to head to Baku which features the longest stretch of flat-out running seen during the season. This will be the ultimate test of deployment.

Watching all this with great interest is Red Bull. With a foot in both the Honda and Renault camps it’s in a unique position for comparison. So far what is has observed of Honda is a level of commitment, open mindedness and rate of improvement exceeding that of Renault. As things stand, it would be a surprise if the senior Red Bull team was not Honda-powered in 2019 and beyond.    

Since he began covering Grand Prix racing in 2000, Mark Hughes has forged a reputation as the finest Formula 1 analyst of his generation