The replacement for displacement

With emission standards becoming tighter and tighter. Vehicle manufacturers are under more scrutiny when it comes to engine emissions. I don't know about you but isn't a little strange that most cars and even some SUVs are starting to ditch V6 and V8 engines in favor of fuel efficient 4 cylinder engines. Not only does the 4 cylinder engine have lower displacement (The total volume of air/fuel mixture an engine can draw in during one complete engine cycle. Commonly measured in liters(L). Typically 4 cylinder engines have 1.5-2.5 Liters of displacement while V6 engines have a displacement of 3.0-4.0 liters and V8 engine configurations go up from there. Typically more Cylinders = more displacement. Until recently it was common to equate higher displacement with more horsepower. For production vehicles that has changed, but how you asked?

Turbo charging

Earlier in the article I mentioned that 4 cylinder engines nowadays have power outputs that rival or surpass their larger displacement counterparts. That is commonly achieved through turbocharging or forced induction.(Forced induction is the process of delivering compressed air to the intake of an internal combustion engine. A forced induction engine uses a gas compressor to increase the pressure, temperature and density of the air. An engine without forced induction is considered a naturally aspirated engine.) Source Forced induction pushes more air into the engine increasing the displacement of the engine thus improving performance and power output. let me explain. a good rule of thumb is that the lower displacement engines typically have better fuel economy. The sacrifice is typically lower power output. What turbo chargers do is increase the displacement. I will now try to explain how this happens without turning this into a physics lesson, please bear with me. At sea level our base atmospheric pressure is around 14.5 pounds per square inch (PSI). That number fluctuates depending on temperature and elevation. Turbochargers add air to the engine thus increasing the atmospheric pressure. Example: 2.0 liter engine can draw in 2.0 liters of air/fuel at sea level for every 14.5 psi of air pressure the turbocharger adds. the displacement doubles. So that 2.0 liter engine is now 4.0 liters. Pretty cool eh? That pressure is commonly referred to as boost. That is why manufactures like Ford refer to there turbocharged engines as "ecoboost".


Fuel economy

As stated before smaller engines typically yield better gas mileage and for larger engines the inverse is true! When you are cruising around town in your turbo charged vehicle you get great gas mileage. However you might have noticed that when you "step" on the throttle your fuel economy is not so great but you have a considerable amount of power. That is because that 2.0L engine just turned into a 4.0L engine and we know that more displacement typically means lower fuel economy but more power power. Physics is Awesome!


If you are worried about a 4 Cylinder engine having enough power or oomph for you and your family's needs, you need not to worry. Example, in 2012 a 3.7L V6 mustang made 305 horsepower(HP). Today a 2.3L 4Cyl mustang makes 310 HP. That is not only true of the mustang either? There are countless examples of this! Don't just take my word for it I urge you to schedule a test drive with me or your local dealer to experience the difference. Technically speaking turbo charged engines are not the replacement for displacement but they are a welcomed addition by improving fuel economy and horsepower!

As always if you have any questions comments or concerns please feel free to leave them below or reach out to us directly at God bless you and have a wonderful day!

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