With five races remaining, consistency will be the key to the 2010 world championship titles, says McLaren chief engineer Phil Prew.

In the latest Vodafone McLaren Mercedes phone-in press conference, Prew claims that his team's continued development of the MP4-25 combined with its reliability will see Lewis Hamilton and Jenson Button close the gap to their rivals.

"It's a big weekend," he said. "There are some big upgrades and I'm confident we've closed the gap. The race will be very close."

Looking at the five race run-in which sees the championship end in Abu Dhabi in November, he said: "Any driver who is able to finish the remaining five races in a competitive position, that is, the top three or four, is going to be dangerous. It comes down to consistency and if any one of the five drivers in contention has a string of five good results they will be in a very strong position to challenge for the title.

"Our target now is to get 10 race finishes, five for each driver," he continued, "and if we achieve that we've got as good a shout as anybody."

In terms of reliability, McLaren has an 85.7% record this season with 24 finishes from 28 starts - 23 of which were points finishes. This compares with Ferrari (27 finishes), Mercedes (26) and Red Bull (25).

Ferrari also leads the way in terms of the total number of laps completed, the Maranello outfit having completed 1658 (99.4%), compared with Red Bull (93.9%), Mercedes (93.6%) and Renault (88%). The Woking team has finished 1460 laps, a rate of 87.5%.

However, Prew is confident that various upgrades, including a new front wing, will see his team take the fight to its rivals. Three of the remaining five tracks - including Sunday's Singapore Grand Prix - are high downforce circuits, the type that suits the Red Bull more than the McLaren. Indeed, at the Hungaroring, the most recent high downforce track on the calendar, the MP4-25 was worryingly off the pace.

"We're optimistic that the gap in Hungary, which was massive by Formula 1 standards, should well have reduced," said Prew. "Coming out of Hungary we all recognised the pace wasn't where it needed to be and since then we've had a whole number of upgrades on the car, some of which were run at Spa and Monza and they will carry over to this race.

"We have further upgrades that we'll see here in Singapore, which is a new front wing and other devices looking to increase the downforce on the car. Also, our understanding of the car, how to exploit the upgrades and how to get the downforce to work for us, has improved since Hungary.

"Our target is to be the fastest car," he continued, "but only time will tell if we've done enough. Hopefully what we've added to the car over the last six weeks will be sufficient to close the gap up."

The Englishman believes that another factor which will aid his team's cause is the tougher load test introduced to detect flexing, Red Bull and Ferrari widely believed to have benefited from said practice for several races from Silverstone onwards.

"The regulations in place now mean that it should be a level playing field and everyone knows the constraints we have to operate to," he said. "That's good for the sport and the teams. The advantage that was felt to be being gained by Red Bull and Ferrari in Hungary, with the new regulations, will be harder to exploit if that is indeed what they're doing."