Only one McLaren is slow in a straight line, and nobody at Woking is entirely sure why. The deficit has shadowed Lando Norris through qualifying in Baku and Sepang, while Oscar Piastri’s sister car has been unaffected.

Norris has now put a number on what it has cost him.

“It’s been a frustrating two weekends trying to figure out what the issue has been and why there’s just been a constant lack of straight-line speed and performance,” he told reporters.

“And especially in this kind of battle we’ve been in, the last two qualifying [sessions] it’s been two or three positions. So, it’s cost me quite a lot,” he said.

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Team principal Andrea Stella puts the top-speed shortfall at roughly one to two kilometers per hour in power-limited parts of the lap, worth around one to two tenths of a second over a full lap. In a tightly packed midfield, that is enough to drop a car several grid spots.

Stella won’t blame Mercedes

Stella has been pointed about where the blame does not lie.

“But at no point we are making a point about power unit. We are just making a point about a lack of straight-line speed,” he said at Sepang.

Autosport reports McLaren has traced the problem to its own fuel system, auxiliary components that sit on the team’s side of the engine installation rather than parts supplied by Mercedes.

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Norris cannot swap the engine

Replacing engine parts to brute-force a fix is not an option. Norris has already used his full season allocation of internal combustion engines and energy stores under the current regulations, and he took a 10-place grid penalty at Spa for a new control electronics unit. Any further change would trigger another penalty of its own.

So McLaren has had to work the problem in the garage, not at the parts shelf, and the team believes the components it has prepared for the Singapore weekend will put the issue behind Norris.

Marina Bay suits McLaren’s car

The circuit itself may help. Marina Bay is dominated by low- and medium-speed corners and short straights, a layout where a top-speed deficit matters less than the aerodynamic grip McLaren has carried through the season.

“It’s obviously also a circuit where straights are not the highest priority and not as detrimental as the last few weekends. But nevertheless, you always want to go down the straights as quickly as you should be able to,” Norris said.

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The championship picture adds to the pressure. Kimi Antonelli arrives at Marina Bay on 320 points, 84 clear of Mercedes teammate George Russell, with seven rounds and three sprint weekends, including Singapore, still to run.

The race starts at 8pm local time on Sunday, 11 October.

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