It appears that the mighty Mercedes AMG F1 team has lost some degree of dominance over the rest of the field for 2018, and in some ways that is true.

Analysis indicates that Ferrari have now matched Mercedes in power but still aren’t quite there in terms of fuel economy.

“We don’t loose time to Mercedes on the straights” admitted Sebastian Vettel in Melbourne. Indeed in China the Red team were comparable to the Silver Arrows with only a difference of 1.5kph on the main straight.

So many are arguing that actually Ferrari have stepped up their game in terms of engine performance but the truth of the situation appears to be a return to the subject of oil burning for performance gain.

The FIA clamped down on teams using oil in the combustion process over the last couple of years, the biggest culprits being both Mercedes and Ferrari. By burning oil that normally is used for cooling and lubrication of the Internal Combustion Engine, these teams have extracted extra engine performance and gain lap time over Renault and Honda.

This year see’s even more restrictions on burning oil, and the FIA are clamping down harder than ever. In light of this, Mercedes appear to have returned to an old specification of oil, last used in 2016. The biggest result being a loss of performance by the 2018 Mercedes Power Unit.

The German publication Auto Sport und Motor confirms this revealing that the reason for the voluntary move by Mercedes is due to the oil rule change mandated by the FIA for 2018. Mercedes wants to be on the safe side with oil consumption. For 2018, only 0.6 liters per 100 kilometers may be consumed in an effort to prevent oil from being introduced into the combustion process for increased performance.

The common practice to allow oil to mix with the combustion process involved the main seal in the compressor of the turbocharger being deliberately made to “leak” so that a pre-calculated amount of oil could enter the combustion chamber. And it appears Ferrari are continuing to do just that.

The FIA ​​is conducting strict oil consumption controls this year. Sensors in the main oil tank constantly measure how much the level drops. Every day, the FIA ​​examines the additional oil tanks in two teams, weighs them full and empty, so that it can not be tricked by clever “leaky” seals.

The FIA limit being set at 0.6 litres of oil consumed per 100km, up until Bahrain both Mercedes and Ferrari were sailing close to the wind by burning 0.58 litres of oil. Mercedes have since throttled back but Ferrari are continuing to run at that level. For clarity, Renault and Honda run just 0.1 to 0.2 a piece.

With a maximum of only three different lubricant specifications are allowed per manufacturer, Mercedes have now already used up 2 changes by reverting to the 2016 spec oil, leaving just 1 oil ‘upgrade’ for the rest of the season.

Mercedes boss Toto Wolff explains the reasons behind the move: “The measurements of the oil consumption are not quite precise. If you operate there on the border, you risk that you sometimes over it. Mercedes can not afford to drive illegally. ”

Should Ferrari play safe and follow suit, we might see the red team have less straight line performance relative to Mercedes.