DRIVERS looking for some respite from sky-high petrol prices should consider changing to a lower grade of fuel, according to one expert.

Consultant Ong Eng Tong, a 40-year veteran of the oil industry, said many drivers think pricier petrols will make their cars go faster - but that is not how it works.

"If 92-octane is sufficient, pumping 95 or 98-octane will not bring about any difference," he said yesterday.

His advice: Check your car manual to find out the recommended grade of petrol.

Many drivers have turned to penny-pinching after the country's four petrol retailers raised their prices on Wednesday - all within the span of eight hours. All but one grade of petrol is now above the $2 mark - a record.

The price hike has forced businessman David Lim to downgrade the petrol for his car. For the past two months, he has filled his Toyota Camry with 95-octane, instead of 98-octane.

"I won't try 92-octane unless I've no choice," said Mr Lim, 55.

But that isn't such a bad thing, according to Mr Ong. Most Japanese and Korean makes will do fine with 92-octane, the lowest grade of petrol available here.

"(Even) 95-octane is good enough for cars from Mercedes-Benz and BMW," said Mr Ong.

"In fact, in Germany, they only have 95-octane."

Before discounts, 98-octane petrol now costs $2.08 a litre, while 95-octane and 92-octane cost $2.006 and $1.973 respectively.

Motorists who make the switch from 98-octane to 95-octane could save $7.40 per 100 litres. Dropping from 95 to 92 would lop $10.70 off 100 litres.

Mr Chua Kim Leng, 40, said he would resort to a more drastic change should petrol prices continue to rise.

Mr Chua, the owner of a 1.8 litre-MPV, said he would consider looking for a smaller car.

Some may abandon the road altogether. Car owner Wong Wan Ying, 44, said: "If prices continue to rise, I might have to stop driving."

Meanwhile, motorcyclists who are already pumping 92-octane are finding other ways to cope with the hike.

Mr Sam Thung, 27, said: "I save where I can. My meals used to cost $3 to $4 but now I go for meals that cost $2.50."

The cook pumps a full tank every day, which costs him $6 - up by about $1 since the start of the year.

Other drivers told the Straits Times they would consider planning their routes more precisely, driving less and taking public transport.