McLaren technical director Paddy Lowe insists the new MP4-27 is a complete overhaul of last year's car and revealed that almost every area of the car has been enhanced.

13216 - More to MP4-27 than meets the eye - Lowe

McLaren unveiled its 2012 car at its factory on Wednesday with the team confident it has the potential to challenge for the championship. On the surface there appeared to be similarities with the outgoing 2011 car, even though the exhaust and nose have been redesigned to meet new regulations. But despite an evolution of the overall concept of the 2011 car, Lowe said the many of the improvements on the MP4-27 are more than skin deep.

"There's great deal of change," he said. "It's in the nature of Formula One now that the regulations are trimming us into narrower and narrower boxes, so inevitably we don't see the big radical changes that we saw in the past from one year to the next.

"This car in many ways looks quite similar, but underneath there's been a great deal of change. Every single part has been assessed and optimised for weight, stiffness and performance in every other respect. When you add all of that up you get a car that's quicker and that's the name of the game. In every area the teams are tasked to find that 1% or 2% because we're looking for that total."

Both Lowe and engineering director Tim Goss said much of the design team's focus has been on making up for lost downforce as a result of the ban on exhaust blown diffusers. This year the exhausts must be positioned higher so that the gases cannot be used to increase the performance of the diffuser, thus limiting rear downforce from 2011.

"Over the last 18 months the performance profit area was all around exhaust blown diffusers, we now have new constraints over the geometry of where we can put the exhaust pipe and what angle it can be directed at," Lowe said. "All of that is intended to keep it high and away from the diffuser, and there have been some restrictions on what we can do with the engine mapping too.

"There's still is a very narrow extent to which you can use exhaust gas to generate performance, but it's much, much reduced from last year. Inevitably we've been looking at ways to make the most out of that in the face of the new constraints."

But despite losing downforce from the ban on blown diffusers, Goss is confident McLaren has made most of it back by improving the overall aerodynamics of the car. For example, he explained that the 2011 car's distinctive U-shaped sidepods had been ditched as they were designed to work with a blown diffuser and did not suit the 2012 exhaust system and tighter rear packaging.

Asked how much performance had been lost as a result of the ban on blown diffusers, he said: "It's drastically reduced and there are geometric restraints which mean you just aren't going to achieve the same performance that you did last year. You have to think about treating the rear end of the car differently and concentrating on un-blown performance as opposed to blown performance.

"We've set ourselves ambitious targets and we expect to recover a lot of what we've lost. You optimise around a certain package and we thought we were particularly good at achieving performance form the exhaust and blown diffuser last year. But you pay prices for that, you pay a price in terms of the base performance of the car. We knew that, they were prices we were and trades that we were accepting and last year it produced the quickest car. This year we've taken those gains back and pushed that area harder. So we hope to get back a lot of what we lost and we'd like to think that we'll go back with an equally competitive car."

Goss also revealed that the MP4-27 was due a major upgrade at the final pre-season test in Barcelona to boost performance ahead of the first race in Australia.

"There's lots of parts on the car that we want to develop and we'll give ourselves the opportunity to do that," he said. "The first test will be about putting mileage on the car, checking the systems and getting familiar with a car with different aerodynamic characteristics, but by the time we get to the third test there will be a significant upgrade package and we'll give ourselves the time to get that learning in and then get the upgrade package in."