Future of engines

Future of engines

(this article was written at the end of 2013)

Starting at the 2013 Geneva Auto Show, we saw the start of a sudden shift towards hybrid supercars with the LaFerrari, Mclaren P1 and now the Porsche 918 spyder.

Also, we see a sudden trend to reduce the number of cylinders. The new BMW M4, for example will have a 6 cylinder engine instead of a V8 engine which was used in the car it is replacing. The M4’s V6 is claimed to be 25% more fuel efficient than the outgoing V8. The BMW X5 will also have two four cylinder engines for the first time. The 2015 Mustang will have an option of a 4 cylinder engine for the first time. A Mustang with just 4 cylinders?? It is rumored that the 2016 Mustang GT350 which is replacing the GT500 may not use the current car’s 5.8 liter V8 but may use a 5.0 liter V8. Formula1 has also seen a constant down-sizing of engines. From a naturally aspirated V12 to a turbo charged V6 which will be used from the 2014 season.

Fig: BMW M4’s inline 6 cylinder engine.

Yes, turbo charging seems to be the answer for higher power outputs with reduction in fuel consumption. AMG have confirmed that they will soon switch to turbo charging. So their brilliant 6.2 liter V8 will become history.  Even BMW M division say there will be a switch to turbo charged engines in the long term. But will this spoil the pure driving pleasure offered by a naturally aspirated engine? Yes, there will be turbo lag. But advanced engineering and the latest technology and materials help in reducing this problem. But, it cannot be eliminated. Hence, a turbo charged engine cannot offer the smoothness of a naturally aspirated engine. Hence, Quattro division of Audi feel that performance cars will not shift to turbo charging. Enthusiasts will definitely be disappointed. They will miss the roar of the V8's and hope that the purity of the cars like the E92 M3 are not lost. The other recent changes are the use of hybrid technology.

Called KERS (Kinetic Energy Recovery System) in supercars and hypercars. These cars use a combination of electric power and internal combustion engines to propel themselves. The electric energy can be used to obtain bottom end torque. This helps engineers to concentrate more on the mid and higher ranges of the I.C.Engines and extract more power from these areas. BMW's i8 uses a hybrid system. The engine is just a 1.5 liter 3 cylinder unit developing 228hp. The battery is a 7.2kWh lithium-ion battery developing 129hp. Combined power output is 357hp. The LaFerrari, Mclaren P1 and Porsche 918 spyder have combined power outputs of 950hp, 903hp and 887hp respectively. Complete electric supercars also exist like the SLS AMG Electric Drive and Tesla Model S.

Fig: Layout of SLS AMG Electric Drive

You don’t have to spend on fuel and the cars are environment friendly. They provide catastrophic level of performance [the SLS has 4 electric motors powering the wheels (1 motor per wheel) having a total power output of 739hp] but they have their drawbacks. Limited range is their biggest disadvantage. They take hours to charge completely and are expensive to buy. To counter this problem, BMW’s i3 comes with an optional gasoline tank which is used to generate electricity and increase range. So what bought about this sudden change?? It is mainly due to the ever increasing fuel costs (supercars have very low mileage and, for higher performance, use high octane petrol which is more expensive than regular petrol) and stringent emission rules which require lesser amounts of CO2 coming out of the exhaust pipes. Whether you like it or not, turbo charging and hybrid technology seem to be the way ahead.