Two decades ago, Mr Tan Wah Kum was an avid racer of radio-controlled scale-model cars.

He enjoyed tinkering with the suspension and engines, and revelled in the thrill of competing against fellow enthusiasts. He was so good at his craft that he even participated in international radio- controlled-car races in Malaysia.

These days, the mild-mannered 44-year-old civil servant races a full-scale car - his trusty blue Subaru WRX.

On many weekends, he can be found kitted-out in helmet and balaclava at motorsport events here or across the Causeway.

The skill set which he developed fiddling with radio-controlled cars in his youth has proven surprisingly transferable to real-life cars.

When he started dipping his toes in motorsports, he was already adept at modifying and setting up a car's chassis and knew how to tweak details such as the camber and toe settings to optimise the car's turn-in and balance.

His radio-controlled-racing experience, coupled with an engineering background, has helped accelerate his learning curve immensely.

He worked as a civil engineer for seven years before making the switch to the civil service in 2004.

He bought his WRX new in 2008 for $78,000 and, over the years, has spent a substantial sum upgrading the suspension, brakes, turbo/ intercooler and electronic control unit, among other things.

The engine currently delivers upwards of 300bhp (a significant increase from its original 227bhp output), but many of the modifications are focused not on extracting more power, but on maximising grip and handling.

Mr Tan is a handy spanner-man himself, having changed his own fuel pump and also fabricated and fitted a boot-mounted methanol injection system which he uses in races.

He was bitten by the motorsports bug after joining his first track-day at Sepang in 2009. After that, he started attending advanced driving clinics.

Since 2012, he has taken part in countless gymkhanas organised by the Singapore Motor Sports Association as well as Grassroots Autotest events run by a group of fellow enthusiasts.

When the association revived the much-loved carpark rally in May after a decade-long hiatus, Mr Tan's WRX was in the line-up.

Across the Causeway, he has done gymkhanas, "time attacks" (where race cars compete against a clock and not against one another) and other events in Johor, Malacca and Shah Alam.

As a self-funded amateur, he has achieved some fine results, having come out victorious in the WRX class at an Autocross event in 2012; second in his class at a DriveRite track event in Malacca last year; and finished on the podium several times in Grassroots Autotests over the past three years.

He drives his WRX to work daily and also ferries his 11-year-old son to school. That, and frequent road trips to Malaysia (his fitness instructor wife hails from Klang) have added to an impressive mileage of 271,000km in under eight years.

Despite being a true-blue petrolhead, Mr Tan is scrupulously law- abiding and avoids speeding on the roads.

"I save my racing for the track," he says.

He adds that participating in races "allows me to satiate my desire for competition within the confines of a safe location. I go home to my family on Sunday nights after these events, ready to start the work-week fresh and well rested the next day".

• The writer is a contributor to Torque, a motoring monthly published by SPH Magazines.