"The biggest hurdle in feeling comfortable in this new hillclimb race car is getting my head around driving a car which is lighter and more powerful than what I am used to. After a few test days I am feeling great in the car. It really is a weapon to drive," Cox said.
After being raced at the recent Leadfoot Festival, the vehicle has received a few modifications and driver-comfort upgrades.
Highlands Motorsport Park - who were behind bringing the Race to the Sky event back this year - general manager Mike Sentch said it would be a great event.
He said there would be a good mix of old competitors and newcomers taking on the 14.5km course, with its 135 corners and climbs over 1000m above the Cardrona Valley.
"I think it's fair to say we can expect intense competition for the two main trophies - the Repco Race to the Sky King of the Mountain and the Possum Bourne Memorial Trophy for the fastest New Zealander - as well as the class trophies."
Cox will be up against the likes of eight-time winner of the race and world-renowned veteran driver Nobuhiro "Monster" Tajima from Japan.
Practice runs and qualifying runs are held on Saturday with racing on Sunday. The entry list was limited to 100 vehicles for the 2015 event.
The Cox Motorsport team are still deciding on whether they will compete in the New Zealand Rally Championship this year, in their Mitsubishi Evo X rally car.
The first round of the New Zealand Rally Championship, the International Rally of Whangarei, was also being staged this weekend.
- Tickets to the Race to the Sky event can be bought online from www.racetothesky.co.nz.