The result will be a complex combination of systems that form the 'power unit', rather than a 'simple' naturally aspirated engine. This makes for an entirely new challenge for the manufacturers of engines or power units as they could be named next year. Optimising such a package will involve a lot more technology and systems management than the current naturally aspirated V8 engines.
The basicsInstead, a new engine formula has been laid out, starting in 2014 and lasting to at least 2020. The regulations strictly mandate a 1.6l V6 engine, backed up with a turbo charger which has its axis parallel to the crankshaft. This turbo may feed its energy to an electrical motor (MGU-H) to charge the batteries.
Inversely, the electrical energy from the batteries can similarly be used to spool up the turbo, or be used by another electric motor (MGU-K) to feed more power to the rear wheels, similarly in operation as to the KERS system that was introduced in 2009.
As the batteries (or capacitors) are also allowed to be charged by the rear wheels through an electrical brake system, the trick is to work out how all these flows should operate, when to best use power from the batteries and when best to harvest energy.
More torque will be the result of these changes, something that initially led Pirelli to ask for wider rear tyres. The teams declined however due to their impact on the rear end aerodynamics of the car.
The increased torque will also require stronger gears in an all new gearbox that will need to house 8 forward gears and one reverse. It is also no longer possible for teams to change gear ratios between races, as each competitor will have to declare the ratios to be used before the first race. However, for 2014 one single change is permitted to cover some unknown variables of introducing the entirely new drivetrain regulations.
Overall, the engines will be shorter while the gearboxes will become longer and perhaps slightly narrower. Low gearboxes will also be particularly interesting as that would make room above the gearbox for cooling elements and most likely also the turbo charger. An increased need for cooling will on the other hand require (slightly) bigger sidepods as they will need to house the water and oil coolers, along with an additional intercooler that is expected to be of roughly the same size as the water radiators housed in the sidepods of the 2013 cars.
Where does the power come fromEven though the combination of systems is complex, it is important to remember that all energy needed to power the car will be extracted from fuel, the same as it was before. Any energy recovery system will focus on extracting energy that would otherwise be wasted.
The difference however is that this amount of fuel is limited, requiring engineers to focus on getting the most power out of the available quantity of fuel.
To enforce this focus, the 2014 regulations limit the total fuel consumption for an entire race at 100kg with a maximum fuel flow limit of 100kg/h. This means that for a 90 minute race, the average fuel flow can only average around 66kg/h, while at the Singaporean GP, which often lasts close to two hours, it will have to be around 50kg/h.
Regulation detailsIn order to still keep the costs a little bit under control, the FIA moved to strictly regulate some parts of the drivetrain, preventing exotic designs to result from engineers' minds.
The engine itself for instance must be a 90° V6 of 1.6l with each cylinder having equal capacity, a cylindrical normal section and a bore of 80mm. There must also be 4 poppet valves per cylinder, 2 for inlet and 2 for the exhaust. It is limited at 15000rpm contrary to the 18000rpm of the V8 engines. It seems however unlikely that this will often be reached, always keeping in mind that the engine will probably run more efficiently at lower rotational speeds.
Direct fuel injection is allowed but limited at 500bar, exactly one injector, one ignition coil and one spark plug per cylinder, all types only allowed if they are present on a list of FIA approved parts. Interestingly however, the rules do allow multiple injections per combustion cycle, something that may help fuel efficiency at lower revs and was not allowed before.
Backing up the engine is the turbo charger, which must be placed with its shaft parallel to the crankshaft and not further than 25mm away from the car's centre line. As the regulations also prevent a 'hot vee' configuration, the exhaust pipes will have to flow around the engine block and up into the turbine. The only real variables for turbo positioning are therefore the height and how far to the back of the engine assembly. It seems most plausible to have the turbo closely behind the engine block, so it can be positioned slightly lower. Variable geometry exhaust or turbine systems are however not permitted.
The MGU-H is the motor that can convert torque from the turbine to electricity in order to recharge the electrical storage (ES). It must be mechanically linked to the turbine but may be clutched. Pumps that could previously only be driven mechanically from the drive shaft can now also be powered by the MGU-H.
Contrary to KERS, the energy storage system is now allowed to be more powerful, but also more strictly regulated. This ES must be 'installed wholly within the survival cell', making a single package located underneath the fuel tank the most appropriate position. Converting the electrical energy to motive power will be done by the MGU-K which must be mechanically linked to the power train ahead of the main clutch, meaning it can only be placed just ahead of just behind the V6 engine block.
Finally, it is specified that the total power unit must weigh at least 145kg, a limit that was repeatedly raised after initial regulation settings. This includes all items, except for the electrical storage components, the standard ECU, the flywheel (if present), liquids and other smaller ancillaries (as specified in Appendix 2 of the Technical Regulations).
Other smaller changes include the specification of engine attachment points, making it easier for teams to change engine supplier.
Upon request from teams, it is also permitted to use an electrical system to modulate the brake pressure on the rear brakes, provided that there is a fallback if the system isn't powered. This was asked to allow better control of the rear brakes, given that the MGU-K will also generate considerable braking power that will be depending on various engine parameters.
The end resultThe result of this raft of rule changes will be a power unit that is able to deliver roughly 600hp from its turbocharged engine, backup up by 160hp during 33 seconds of a lap. The most important difference will be the increased amount of torque also at lower revs due to the possibility of the MGU-H to eliminate turbo lag by keeping the turbine at high speed.
Packaging will be interesting, especially the locations of the MGU-H, MGU-K and the turbo. The below image for instance shows just one possibility, but there are an endless amount of possible variations regarding the exhaust piping, whether to position the MGU-K ahead or aside the engine block, and where exactly to put the MGU-H.
Also shown are the larger radiators, items that will be hard to still get into the sidepod when positioned vertically, as Ferrari have done in recent years. Their first video of the new engine though appears to suggest a forward incline of the radiator and intercooler items, although that is just speculation at this point.
It is also important to know that even though the ERS has been extended in power, it will now be entirely controlled by the ECU, eliminating the 'boost button'. Teams will invest many hours to find out when to best use the electrical energy that gets stored in the ES, helping overall laptimes but eliminating the possibility to use this energy for a passing manouvre.
In essence, it's a new engine challenge that F1 hasn't seen in a long time, and one that will spring various surprises and technical issues, especially at the beginning of testing at the end of January. After all, dyno testing never combines the entire package.
Car renderings by Marcos Smirkoff