The AC/DC lead singer is a car nut. But he’s clearly not a member of the more-money-than-sense club. Back in Florida where he lives, he has a garage full of cars, each carefully, if somewhat randomly, chosen.

There is a twin-engined Vespa car, a 1928 4.5 litre Bentley, race cars which he pilots with aplomb, an Audi R8 and a Citroen DS23 Pallas – possibly the most beautiful car ever made.

There’s also a giant black Rolls-Royce Phantom of the kind that graces the cover of his recently released automotive autobiography Rockers and Rollers.

“I am after something really … special,” he says as he flicks through a glossy American luxury car magazine looking for inspiration. “The Ferrari 458 is pretty. I like the new Merc SLS [Gullwing] too.”

While Johnson has enjoyed international stardom for the past 30 years grace of his involvement with one of the most successful rock bands of all time, his love of cars has recently earned him his own place in the spotlight.

After an appearance on the BBC’s Top Gear last year in which he revealed his long association with all things automotive, he found his legion of fans expanding outside the traditional AC/DC base.

“Jeremy [Clarkson, Top Gear host] and the boys were fans of the band and their producer called up one of our guys to get some tickets for a gig,’’ he says.

‘‘They came back stage and we were talking and Jeremy literally just asked me if I’d fancy going on Top Gear. I said I’d kill to get on Top Gear. It’s me favourite show.”

As with all guests, Brian lapped the track in a cheap family saloon. But with some serious race experience under his belt (he competes in a sports car series in America), he blew the doors off the car and the top off the celebrity lap time board.

“I had a ball,” he says later as he sits behind the wheel of a Rolls-Royce Drophead Coupe for a driving tour of Sydney.

“Honestly, I didn’t think I’d come anywhere near the top and to get ‘the fastest man of 2009’ award was just icing on the cake for me.’’

Not that the reward for taking the top honour was that impressive. ‘‘It must have been the cheapest trophy in the shop,’’ he says.

‘‘They spelt me name wrong and there was an ice hockey player on the top. It was awful. So when I was speaking to the guys, I said, ‘I’ve got a special place to keep this forever and that’s in the loft.’

No really, I unashamedly have it on my pub bar at home. It has pride of place, and it’s so awful that it’s brilliant!”

Frustratingly for someone who loves driving, Johnson’s lifestyle and touring commitments mean he can go weeks or even months without getting behind the wheel. Transport to gigs usually comes in the form of a police-escorted convoy.

“But if I had to drive the band to a gig, it would be in a Rolls,” he says.

“Imagine driving this on the road to Perth across the desert. The boys had an old tour bus in the early days and it took forever to get there and the sun was always in your eyes and the heat and that’s where [former lead singer Bon Scott] came up with the words to Highway to Hell. Little bit of Australian history and AC/DC history there for you…”

As well as his concert commitments, Johnson is using his visit to Australia to make a three-part film on his travels. The project sees him drive in three countries. In Sydney he cruises through the city to Bondi Beach, in the UK across the north of England, and in the US through the Deep South.

“Why we picked this drive to Bondi and around Sydney is because the city is just so beautiful and it is the birthplace of the band,’’ he says.

‘‘The sights and scenery that you have here. And you’re right in the middle of one of the biggest cities in the world so it might strike people as strange, but bollocks – that’s what I like.”

Johnson tillers the Rolls from the Park Hyatt hotel round under the Harbour Bridge. Tourists making the Bridge Climb spot the car, then the star, and holler down. Johnson is not the only star beneath the bridge. F

ellow car nut Ronan Keating is out making his own film. The two singers and their entourages have an impromptu pow wow. Keating wants to know how come he is walking and why Johnson is in a Rolls.

“For years and years I never bought one because people might think I’m showing off,’’ he says. ‘‘Then I thought, ‘Do I want to be sat on my deathbed thinking that the one thing I wanted to do in life was buy a Rolls-Royce but I didn’t because I was afraid I’d look like a prat?’ Bollocks! These cars are great and if you win the lottery, buy one.”

Johnson says a car also played a part in him landing the gig with AC/DC after the death of Scott.

Called up for an audition, he had no way of getting to London from Newcastle until a friend lent him a chocolate brown Toyota for the journey. Despite a puncture on route, and a surprising choice of Ike and Tina Turner’s Nutbush City Limits as his audition, Johnson got the gig.

“The car got me the job,” he laughs.

Then, when his first pay cheque came in, it’s no surprise he spent it on a car. His first new car after years of secondhand models.

“The cheque was for $30,000 – my house wasn’t worth that. It was crazy. I went out and bought the daftest thing. A Chevy Blazer. I loved it. It was big. The only thing like it was the Range Rover. It was black and white...the same as Newcastle United’s colours.”