By Christopher Tan, Senior Correspondent

Institutional trader Bernard Chin and portfolio manager Willy Ballmann could probably afford to buy their own sports car. But they chose to build one instead.

Mr Chin, 36, and Mr Ballmann, 33, have just completed assembling an Ultima S, a fibreglass supercar powered by a high-compression, naturally-aspirated 7-litre 650bhp, 810Nm Corvette engine.

It took them about 800 hours over the course of a year to finish the job. And the satisfaction of hearing the low-slung rear-wheel-drive two-seater roar to life made it all worth the trouble.

'We wanted to build our dream car,' said Mr Ballmann, a married German who has been living here for 12 years.

'It was something interesting and creative.'

Mr Chin, a single Singapore-born American who has been here for five years, said the project, possibly the first of its kind here, was 'fun and something innovative we just had to do'.

ULTIMA S: Willy Ballman working on the chassis of the fibreglass automobile.

Their idea was to combine the raw efficiency and power of a stripped-down racing car with the elegance and comfort of a grand tourer.

'Most importantly, we designed the project in such a way that it would pass all the tests for road legality in Singapore,' said Mr Ballmann, a Cambridge mathematics graduate.

They started with an FIA-approved steel-tube chassis and the body of an Ultima GTR, sourced from Ultima Sports, a British supplier of self-build cars.

Everything else - from wiring to interior architecture to metalworks - were done by them with the occasional help of workshops and fabricators here.

'It was a steep learning curve. We found out there are actually quite a lot of automotive expertise at the local garages,' said Mr Chin, who studied electrical engineering and computer science at the Massachusetts Institute of Technology.

Mr Ballmann added: 'Equipment to weld aluminium is not something you keep around the house.'

But why bother?

'The great thing about a customised car is you can control every nut and bolt, and assembly,' he explained.

'Everything is up to how you want to build it.'

For instance, they picked a five-speed manual gearbox from Porsche because they needed something to handle the power plant's immense torque. They had to source for a special battery that could crank up the enormous engine.

They kept the car's weight to around 1,000kg.

'We picked the Ultima because it is very light and aerodynamic,' said Mr Chin, whose daily ride is a Lexus GS300.

It is no coincidence that the finished product is a hint of McLaren F1. In 1991, the McLaren Group picked Ultima as the basis for prototyping its supercar.

What was it like building your own car?

'It was like doing a gigantic 3-D puzzle,' said Mr Ballmann, who drives a Honda Civic Hybrid.

'But we did not just piece things together. We had to make sure vital components remain accessible for repairs.'

3D PUZZLE: The 7-Litre engine being lowered into the engine compartment

The pair will consider turning their hobby into a commercial concern if there is demand for the car. But they do not have a price in mind yet (and they will not reveal how much they spent on the project).

Their immediate plans are to get the car on a track, as well as to get it approved by the Land Transport Authority for road use.

This article was first published in The Straits Times on Nov 8, 2008.

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