The following regulations will apply to the 2005 Formula 1 Season:
Engines:
Each engine must last for two complete Events.
From the 2005 Formula 1 Sporting Regulations:
Spare Cars and Engines
85) Each driver may use no more than one engine for two consecutive Events. Should it become necessary for a driver to use another engine he will drop ten places on the starting grid at that Event and may not use another engine until the end of the next Event. Any driver who failed to finish the race at the first of the two Events may start the second with a different engine without incurring a penalty.
However, should an engine change be carried out after the first qualifying practice session but before the race at either of the two Events, any drivers concerned will be required to start the relevant race from the back of the starting grid in accordance with Article 126.
After consultation with the relevant engine supplier the FIA will attach seals to each engine in order to ensure that no significant moving parts can be rebuilt or replaced. Following the first of the two Events further seals will be applied in order to ensure that the engine cannot be run until the second Event unless it is installed in the car concerned.
Other than the straightforward replacement of one engine unit with another, a change will also be deemed to have taken place if any of the FIA seals are damaged or removed from the original engine after it has been used for the first time.
Tyres:
One set of tyres must complete qualifying and the race.
From the 2005 Formula 1 Sporting Regulations:
74) Quantity and type of tyres
a) During the Event no driver may use more than four sets of dry-weather tyres, four sets of wet weather tyres and three sets of extreme-weather tyres.
If a driver change is made during an Event the tyres allocated to the original driver must be used by the new driver.
From the four sets of dry-weather tyres each driver will be allocated two sets of differing specification for use on the first day of practice.
For the purposes of the above a set of tyres will be deemed to comprise two front and two rear tyres of the same specification.
Before 08.00 (or 07.00 during Events taking place in North America) on the second day of practice each driver must nominate which specification of tyre he will use for the remainder of the Event. However, if both free practice sessions on the first day of practice are declared wet this decision may be deferred until 12.00 (or 11.00 during Events taking place in North America).
Unless the use of wet or extreme-weather tyres is necessary one of the remaining unused sets of dry-weather tyres must be used for both of the qualifying sessions, all reconnaissance laps and the entire race. Unless a precautionary tyre change is necessary for clear and genuine safety reasons, only a punctured or damaged tyre may be changed during a race. No refuelling will be permitted whilst a car is in the pits for the purposes of changing a tyre.
Aerodynamics:
Bodywork Changes to the bodywork (aerodynamics) to raise the front wing, bring the rear wing forward, reduce the diffuser height and cut back the bodywork in front of the rear wheels.
From the 2005 Formula 1 Sporting Regulations:
3.7 Front bodywork height
3.7.1 All bodywork situated forward of a point lying 330mm behind the front wheel centre line, and more than 250mm from the centre line of the car, must be no less than 150mm and no more than 350mm above the reference plane.
3.7.2 All bodywork situated forward of the front wheel centre line must be no less than 50mm above the reference plane.
3.8 Bodywork in front of the rear wheels
3.8.4 With the rear wheels removed and when viewed from above, no bodywork more than 500mm from the car centre line may lie between the rear wheel centre line and a point 400mm forward of it. Any bodywork forming the forward inner corner of these areas may have a radius no greater than 140mm.
3.10 Height behind the rear wheel centre line
3.10.1 Any part of the car behind the centre line of the rear wheels must not be more than 800mm above the reference plane.
3.10.2 No bodywork behind the centre line of the rear wheels, and more than 150mm each side of the longitudinal centre line of the car, may be less than 300mm above the reference plane.
3.10.3 Any bodywork more than 150mm behind the rear wheel centre line which is between 300mm and 600mm above the reference plane, and between 75mm and 480mm from the car centre line, must lie in an area when viewed from the side of the car that is situated between 300mm and 375mm above the reference plane and between 150mm and 500mm behind the rear wheel centre line. When viewed from the side of the car no longitudinal cross section may have more than one closed section in the lower area.
Any bodywork behind the rear wheel centre line which is more than 375mm above the reference plane, and between 75mm and 480mm from the car centre line, must lie in an area when viewed from the side of the car that is situated between 600mm and 800mm above the reference plane and between the rear wheel centre line and a point 350mm behind it. When viewed from the side of the car, no longitudinal cross section may have more than two closed sections in the upper area. Furthermore, the distance between adjacent sections at any longitudinal plane must not exceed 15mm at their closest position.
In side view, the projected area of any bodywork lying between 300mm and 800mm above the reference plane and between the rear wheel centre line and a point 600mm behind it must be greater than 230000mm².
3.12 Bodywork facing the ground
3.12.6 To help overcome any possible manufacturing problems, and not to permit any design which may contravene any part of these regulations, dimensional tolerances are permitted on bodywork situated between a point lying 330mm behind the front wheel centre line and the rear wheel centre line. A vertical tolerance of +/- 5mm is permissible across the surfaces lying on the reference and step planes and a horizontal tolerance of 5mm is permitted when assessing whether a surface is visible from beneath the car.
3.12.7 No bodywork more than 150mm from the car centre line, which is visible from beneath the car and which lies between the rear wheel centre line and a point 330mm forward of it may be more than 125mm above the reference plane. Any intersection of the surfaces in this area with a lateral or longitudinal vertical plane should form one continuous line which is visible from beneath the car. Additionally, any bodywork in this area must produce uniform, solid, hard, continuous, rigid (no degree of freedom in relation to the body/chassis unit), impervious surfaces under all circumstances.
2005 Formula 1 Qualifying System
Saturday Afternoon Session (13:00 to 14:00 )
Single lap qualifying with the cars going out in the reverse order of their finishing positions at the previous race.
No restrictions on fuel load
Sunday Morning Session (10:00 to 11:00 )
Single lap qualifying with the cars going out in the reverse order of the qualifying on Saturday (fastest car on Saturday goes out last on Sunday)
Session to run with race fuel load. (no refuelling allowed prior to the start of the race)
Times from the two sessions are added and the grid is determined with the shortest aggregate time on pole.