Formula One's new rules have succeeded in slowing cars and cutting costs significantly, International Automobile Federation (FIA) president Max Mosley said on Thursday.

Hailing an "excellent start" to the season, Mosley congratulated tyre and engine suppliers for their efforts.

"The drop in performance predicted by the Formula One technical directors has been achieved in the first two races," he said in a statement.

"Had the rules not been changed it is reasonable to assume that the reduction in lap times [increase in speeds] from 2004 to 2005 would have been about the same as it was from 2003 to 2004," added Mosley.

The FIA pushed through rules changes on safety grounds last year after expressing concern that cornering speeds were becoming too dangerous.

Engines must now last for two successive Grands Prix, twice the previous distance, while drivers must use the same set of tyres for qualifying and the race.

By way of illustration, Mosley said the best race lap times in Australia and Malaysia were 1.6 and 1.3 seconds slower respectively than they had been in 2004 but still considerably quicker than 2003.

Had the rules not been changed, the Briton argued that the lap times in the opening two races would have been 3.6 and 2.2 seconds quicker respectively than last year.

"Assuming that normal progress would have been made had the rules not been changed, the cars were 5.2 and 3.5 seconds a lap slower in Australia and Malaysia respectively," he said.

BIG SAVINGS

Despite some manufacturers saying the new rules have done nothing to cut their costs after being forced to redesign engines before even more sweeping changes next year, Mosley said the savings were significant.

"We understand that the tyre suppliers are now taking four sets per car to a Grand Prix compared to 19 sets per car in 2004," said Mosley.

"Also each team is now using two engines for two events.

"Had the rules remained the same as in 2002, top teams would now almost certainly be using 12 engines for two events [one practice engine, one qualifying engine and one race engine per car per event].

"Bearing in mind that an engine rebuild costs about $200,000 and remembering that these engines now last upwards of four times as long during private testing, the savings are enormous," said Mosley.

"There is also a significant saving on capital expenditure because each team's stock of engines and wheels is smaller. With fewer engines and wheels to move around the world transport costs are also lower."

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