Compared with many vehicles in this year's event, the Tilton Evo has undergone relatively minor upgrades since last year's WTAC. A Cosworth-spec engine adds 60kW, bringing the total to around 600kW. This extra power now goes through a new six-speed sequential transmission.
MCA Suspension refined the existing shock absorber set-up, and the suspension cross members were replaced with some hand-fabricated items. The aero kit was also replaced with a new, lighter set-up. This and some other part changes have brought the weight down to around 1180kg. Garth said the difference delivered by these changes have been substantial.
"We've gained good time around some familiar tracks, so it's obvious to us that the time spent on the car is paying off," Garth said. "The new aero, the engine and the change to Hankook tyres will give us the edge we need.
"Our goal is to win. Our car is a whole lot better than last year and we're feeling pretty confident that we can do it."
Organiser of this year's WTAC at Sydney, Ian Baker, said the intensity of development aimed at setting the fastest flying lap on semi-treaded street-legal tyres is "mind blowing".
"World Time Attack has become an arms race to see who can build the lightest, most powerful and most aerodynamically effective car - and this year the Australian teams have really stepped up to try and meet the standard of the overseas squads," he said.
The official launch of WTAC 2012 will take place tonight, August 2 from 7:00PM at Westfield Parramtta's centre court, where a number of competing cars will be on display.
The World Time Attack Challenge will run from 10 to 11 August at Sydney Motorsport Park (Eastern Creek).