Don't forget the F1 race in Australia this week end; here the new 2004 rules: Subtle but important changes have been made to the Formula One regulations for the 2004 season, affecting both cars and the Grand Prix weekend format. Here is a summary of the key points. Third cars and Friday practice: The private test and first qualifying sessions seen on Fridays last year have been abandoned for 2004. Instead the opening day of the Grand Prix weekend will comprise two one-hour practice sessions. In these, all teams bar Ferrari, Williams, McLaren and Renault (the top four in the 2003 constructors championship), will be allowed to run a third car. The driver of the third car cannot be one of the teams nominated drivers for that event and must be in possession of a Super License. He must also have taken part in no more than six Grands Prix in the previous two seasons. Third cars will be allowed to run in non-standard livery, paving the way for race-specific sponsorship deals. Qualifying: Saturdays schedule will, as in 2003, feature two 45-minute practice sessions, which will be followed by a new two-part qualifying session, effectively 2003s Friday and Saturday sessions back to back, with just a two-minute break in between. In the first part of qualifying the starting order will be determined by the finishing order from the previous race, with each driver getting one timed lap. In the second part they will get another timed lap, running in the reverse order of the times set in the first part. Refuelling will be allowed during the first part of qualifying only. As in 2003 though, set-ups and fuel loads cannot be altered between the end of the second part of the qualifying and the race. Tyre choice: Last year teams could wait until after Saturday practice to decide which tyres they would use for qualifying and the race. This season that crucial decision will have to be made earlier by 0900 on Saturday morning (before first practice). The only exception will be if both Friday sessions were wet, in which case the deadline will be extended to 1300 on Saturday (after practice). Driver Aids: Launch control has been banned for 2004 meaning that drivers will once again have to use a clutch mechanism to get the car off the line at the start of a race. In a related move, fully-automatic gearboxes have also been outlawed, meaning drivers must make all gear changes themselves (even if those changes are clutchless, using paddles or buttons mounted on the steering wheel). Traction control remains legal. One engine per weekend: In a bid to cut costs, this year every driver is allowed to use only one engine over the course of the Grand Prix weekend. If his engine fails in either Friday or Saturday practice he will drop ten places on the grid from his qualifying position (for example, if he qualifies fifth, he will start from 15th). If his engine fails during qualifying he will start the race from the back of the grid. Aerodynamic and bodywork changes: In a move designed to reduce downforce (and hence cornering speed), this year the cars rear wings may feature no more than two main, horizontal elements. The end plates on either side of the rear wing have also been made bigger, as has the engine cover, allowing more space for sponsor logos. Pit lane speed limit: At most events the pit lane speed limit during a race will be raised from 80 to 100 kph. This will make for quicker stops and could have an important impact on teams strategies. For example, the opening round in Australia (where the pit lane has also been shortened) may well become a three, rather than a two, stop race.