McLaren are racing to develop ride height control systems that they had thought would be illegal but which Formula One rivals Red Bull seem to be using to their advantage, Martin Whitmarsh said on Saturday.
"I think there's some evidence that there are ride height control systems which many people wouldn't have thought were permissible," the team boss told BBC television after Red Bull swept the front row at the Australian Grand Prix.
"As you can imagine, we are working quite hard on those systems now.
"The original rulings suggested that such systems wouldn't be allowed on cars. (We are) seeing some cars now that seem to me to have those so we've got to have those fitted as quickly as we can," the Briton added.
"Hopefully by China we'll have something on the car."
The Chinese Grand Prix, on April 18, is the fourth round of the season. Red Bull's German Sebastian Vettel has taken pole position in the two races so far this season.
McLaren's Jenson Button will start Sunday's race from fourth place on the grid while his British team mate Lewis Hamilton occupies 11th place after a disappointing qualifying session in Melbourne.
Asked by former McLaren and Red Bull racer David Coulthard, who acts as both a television pundit and a consultant to Red Bull, who might have such systems, Whitmarsh replied:
"I think it looks like Red Bull and some other cars are able to run lower in qualifying than you would expect if they are then going to fill the car with fuel afterwards."
Formula One commentators have highlighted how the wooden plank on the underside of the Red Bull car occasionally appears to scrape the surface of the track, sending out puffs of dust, while qualifying on low fuel.
They have surmised that there must be a mechanism to restore the ride height when the car then starts the race with a full tank.
The regulations have since 1993 banned active ride systems, pioneered by the original Lotus team and then used to great effect by Williams, but a ratchet device could have a similar effect without being illegally powered.
The advantage would come in the final phase of qualifying, with the cars able to run lower on the ground than rivals before then starting the race on a similar ride height.
Whitmarsh's comments, at the second race of the season, came after Red Bull boss Christian Horner triggered a controversy over the McLaren's rear wing in the run-up to the championship opener in Bahrain.
Renault F1 managing director Bob Bell said at Sakhir that he felt the McLaren wing was "fundamentally illegal" and a breach of the spirit of the rules and regulations.
However, Horner conceded at the time that the governing FIA had looked at it and deemed it legal, adding that "it's therefore a clever design as opposed to illegal design".