By TONY NG

RUNNING in your new car.

Some fanatics swear by it, others dismiss it as unnecessary.

There's a whole slew of theories in magazines and on websites about this "art" - from changing oil to not tapping your accelerator too hard.

So, what's the gospel truth?

Because of minute imperfections that occur in manufacturing, mechanical components are uneven and these are mated to other parts.

Running in - a process that occurs in the first 1,000 to 1,500km - enables these imperfections to be evened out through beneficial wearing.

A proper run-in can give several benefits.

Besides letting you get comfortable with your new ride, it will also increase the lifespan of your engine and improve its fuel consumption.

If you are buying a car with a manual transmission, a run-in period will also smoothen gear changes, says Mr Shreejit Changaroth, the resident tech guru of Torque, Singapore Press Holdings' monthly motoring magazine and owner of a mechanical- engineering firm.

Says Mr Changaroth: "All the parts used in the car are mechanical bits set to certain tolerances - they need a minimum amount of wear for the parts to fit perfectly."

He drew an analogy between that and wearing new shoes.

"It takes a while before the shoes fit the shape of your feet perfectly and you feel comfortable."