As further support of National Motorsport Week, two of the UK-based Formula One teams - Mercedes and Team Lotus - are each inviting two members of the public to join their respective pit crews at the forthcoming events.

The four lucky winners joining either Team Lotus or Mercedes for a memorable day will be selected at random from those entering a simple competition hosted on the Gomotorsport website. The promotion opens today (20 June) and will close at midnight on Friday 24 June when a series of competitions to win factory tours at all eight UK-based F1 teams will commence. Terms and conditions apply and are detailed on the website.

As fully-uniformed members of the team, two winners will join Mercedes at the Goodwood Festival of Speed on either 2 or 3 July. They will assist in the preparation and running of the team's entry in the world-famous hill climb, providing an experience of a lifetime opportunity to see the operation of a Formula One team from the inside and enjoy the Festival from a unique perspective.

The two other winners will join Team Lotus at a forthcoming straight-line test at the Kemble Airfield, near Cirencester in Gloucestershire on either 4 or 5 July. They, too, will gain a rarely seen insight into the workings of a modern Grand Prix team.

Alongside a wide range of initiatives and activities taking place up and down the country at teams, venues, businesses and motor clubs, McLaren will be offering its own support to National Motorsport Week. Britain's most successful F1 team will be acknowledging and rewarding the legion of volunteer marshals who give up their time to ensure the smooth running of thousands of motor sport events staged in the UK every year. Recognising their contribution, McLaren is offering all registered marshals the opportunity to visit the state-of-the-art McLaren Technology Centre in Woking later in the year via a special competition which, again, will be hosted on the GoMotorsport website during National Motorsport Week.

Backed by the Motor Sports Association (MSA), the UK's governing body of motorsport, and the Motorsport Industry Association (MIA), National Motorsport Week exists both to highlight the UK's on-going world-leading role in all areas of international motor sport as well as to showcase the wide range of opportunities open to enthusiasts at grass roots level throughout the country.

"We are delighted that all eight of the UK based Formula One teams are supporting National Motorsport Week by providing the public with so many special 'money can't buy' opportunities," said Colin Hilton, Chief Executive of the MSA. "We have already announced an amazing line up of factory tours giving members of the public are rare chance to see the inner workings of a Grand Prix team and now Team Lotus and Mercedes are taking that one step further by inviting four lucky winners to join their teams for very specials day at Goodwood and Kemble. McLaren's offer is equally generous. Whether it's the thousand plus volunteers helping to stage the Santander British Grand Prix at Silverstone or the handful of enthusiasts running a Sunday morning autotest, British motor sport wouldn't be possible without their support. Initiatives like this provide them with some well earned respect and reward."