After speeches and champagne at the futuristic and pristine Woking factory, with employees wearing the 'rocket red' shirts normally donned after a victory, it was back to preparing for Sunday's Italian Grand Prix at Monza.
Their current race drivers, the 2009 champion Jenson Button and Mexican Sergio Perez, later attended a gala premiere in London of the new movie 'Rush' about the 1976 title battle between James Hunt and Niki Lauda, who were both McLaren world champions.
There will be more glasses raised at Monza to toast the milestone but the real celebrations will come only if there is a win again and for that the team is likely to have to wait until next season.
Fifth place, for the team who ended last year with the fastest car and a win for Button in Brazil, is their best result in 11 races so far and already the focus is moving to 2014.
Button, who won his title with Brawn GP, was sure the team would be contenders again.
"I grew up watching this team achieving great things with Ayrton Senna and my racing hero Alain Prost," said the Englishman in a tribute on the team website (www.mclaren.com).
"And I firmly believe this team will be great again. This is an organisation you can never discount. Their appetite for winning is unlike anything I've ever seen and, rest assured, we will be back at the front soon."
McLaren is Formula One's second most successful team after Ferrari, in terms of race wins and total titles, and the second oldest still competing uninterrupted since their foundation.
Bruce McLaren Motor Racing Limited was founded on Sept 2, 1963, when the New Zealander was 26 years old, with a small group building cars in a workship in New Malden, south of London.
McLaren died in a testing accident at Goodwood in June 1970, before the team tasted real success and before the years of dominance under former principal Ron Dennis, now group chairman.
The workforce has grown to more than 2,000 people employed across a range of companies.
The team have won eight constructors' titles between 1974 and 1998 and 12 drivers crowns between 1974 and 2008, with Lewis Hamilton their most recent champion and Brazilian Emerson Fittipaldi the first.
In 1988 and 1989, with Alain Prost and Ayrton Senna, they won 25 of 32 races.
Hamilton has now left for Mercedes, with what many condemned as an unwise decision now looking like a smart choice with the Briton a winner again while McLaren are facing one of their blank years.
McLaren, who made their debut in 1966 with the founder himself taking a first win in 1968, can still boast that no team has won more than their 182 victories since they entered the championship.
Glamour team Ferrari have a tally of 221 - but 39 of them were won before 1966.