A CAR-BOMB paymaster had his nine-year jail sentence increased to 14 years yesterday. The device had been timed to explode when the driver was in the vehicle, the Court of Appeal was told. Increasing Yim Chun-leung's sentence, the court agreed it was a miracle no one was hurt even though the vehicle was wrecked. Delivering the Court of Appeal's judgment, Mr Justice Mortimer said: ''Public abhorrence for this type of offence, which puts ordinary members of the public in serious danger, is obvious.'' The eight-year jail sentence for Yim's brother-in-law, Wong Kwan-pak, was also increased to 14 years. The five-year sentence for the man who made the bomb, Law Tin-ho, went up to seven years. But the court did not believe the five-year prison term given to a fourth man, street sleeper Cheung Shu-tai, 55, was either wrong in law or manifestly inadequate. The role he played was minimal and the reason he was recruited was not clear, the court held. Law, 30, had admitted causing an explosion and had testified for the Crown in the trial of Yim, 32, Wong, 21, and Cheung who had all denied the joint charge. The Crown had asked for the Court of Appeal review because it was not satisfied with the jail sentences imposed by Deputy High Court Judge Yeung. The court heard that on August 13, 1992 a bomb attached to the underside of Ho Kwong-leung's vehicle in a Causeway Bay car park exploded, damaging it and other nearby vehicles. Mr Ho escaped death or serious injury only because he noticed a plume of smoke as he approached his car and was fetching a fire extinguisher when the car blew up. Inquiries revealed that Yim, a former business associate of Mr Ho, wanted him killed or seriously injured. Yim asked Wong to help, who in turn recruited Law who had access to explosives. Law made the bomb and planted it with Cheung's assistance. Darryl Saw, for the Crown, told the Court of Appeal the gravity of the offence justified a higher starting point for sentence than the 12 years adopted by the trial judge. Furthermore, the discount given to them was too generous, he said. Mr Justice Mortimer, sitting with Vice-President Mr Justice Power and Mr Justice Mayo, said the trial judge's reasons for sentence and the mitigating features he took into account could not be flawed. However, he said, he had made two errors: the 12-year starting point and the amount of discount he gave. Mr Justice Mortimer said it was the opinion of the court that the starting point ought to be in the region of 15 years. He said although it was a serious offence calling for heavy punishment, there were more serious offences of the same nature, such as terrorist bombings.