Several years ago we mentioned that enhanced by a turbochargers engines in cars would diminish in the number of cylinders, and displacement.
Our thought process at the time mentioned that a V8 would be replaced by a 6 cylinder and a 6 cylinder would be replaced by a 4 cylinder.
In 2015 there is a rash of turbocharged 4 cylinders powering a myriad of vehicles.
Its an inexpensive way to generate more horsepower, and especially torque from a smaller displacement. In 2015 the most popular smaller displacement is a 4 cylinder.
Without the aid of technology turbo motors would still display some erratic characteristics, and not torque up the way they do.
Obvious that 6-7-8 speed automatic transmissions are a true benefit to make a 4 cylinder even with a turbo, seem to have more power.
Front Wheel Drive:
Most if not all platforms using a turbocharged 4 cylinder are front wheel drive. Agreed they might have morphed to all wheel drive. Its almost surprising the low level of torque steer with the majority of these applications.
You know the saying "You need gas to make horsepower" we have noticed that the 4 cylinders that truly torque up, are less economical that the 4 cylinders that are more sedate, or have different modes. In general these engines powering a CUV on the highway are not that economical from our perspective.
The optics of fuel economy appeal, and sell.
Yes...when you increase the air flow in any engine above atmospheric pressure, there is a fine line and trade off between power and durability. In addtion to increased complexity.
There is a "rush" by all manufacturers that have a "generic" 2.0L Turbocharged 4 cylinder as a price leader especially in entry level "premium economy" vehicles. The belief seems to be "If you don't have a 4 with a turbo you are missing out".