It's no secret that an engine, any engine, is basically just a glorified air pump. In naturally aspirated form, a four stroke 2 liter piston engine moves approximately 2 liters of air through it with every two revolutions of the crankshaft.
There are outside influences on this, such as volumetric efficiency, temperature, restrictions in either the intake or exhaust, ambient air pressure, and probably a couple others that when factored in, all limit the actual airflow, albeit only slightly. Because different engines inherently have different restrictions, to me it seems more appropriate to designate engines based off of a measured maximum airflow, rather than displacement.
This is where the turbo comes into play. As boost pressure increases, the airflow requirement does also. Theoretically speaking, a heavily boosted 4G63 can have the same maximum airflow requirement as the NA 8.3 liter Viper V-10, or even more.
The reason I bring all of this up is simple. After any Mustang or Camaro or insert car name here owner has been on the receiving end of the Mitsubishi Pimp Hand, the response I get most often is "No fair!, you have turbo!".
My answer has been that "I'm only running 14 lbs. which is only twice the ambient air pressure, and your 350 is nearly three times larger than my engine, so even with the boost, you still have more engine than me." Usually this confuses them enough that they just drive away.
The problem that I'm having is that I know it isn't that simple. The math is much more complicated I think. I know that power output is increased as the cylinder pressures increase. I think this could one of those exponentially decaying functions (thank you Barnes), and if that is the case, there isn't any real purpose to classifying engines based off of an airflow requirement, because two completely dissimilar engines can exist with the same airflow requirement, and make vast differences in power output.
Please discuss.
There are outside influences on this, such as volumetric efficiency, temperature, restrictions in either the intake or exhaust, ambient air pressure, and probably a couple others that when factored in, all limit the actual airflow, albeit only slightly. Because different engines inherently have different restrictions, to me it seems more appropriate to designate engines based off of a measured maximum airflow, rather than displacement.
This is where the turbo comes into play. As boost pressure increases, the airflow requirement does also. Theoretically speaking, a heavily boosted 4G63 can have the same maximum airflow requirement as the NA 8.3 liter Viper V-10, or even more.
The reason I bring all of this up is simple. After any Mustang or Camaro or insert car name here owner has been on the receiving end of the Mitsubishi Pimp Hand, the response I get most often is "No fair!, you have turbo!".
My answer has been that "I'm only running 14 lbs. which is only twice the ambient air pressure, and your 350 is nearly three times larger than my engine, so even with the boost, you still have more engine than me." Usually this confuses them enough that they just drive away.
The problem that I'm having is that I know it isn't that simple. The math is much more complicated I think. I know that power output is increased as the cylinder pressures increase. I think this could one of those exponentially decaying functions (thank you Barnes), and if that is the case, there isn't any real purpose to classifying engines based off of an airflow requirement, because two completely dissimilar engines can exist with the same airflow requirement, and make vast differences in power output.
Please discuss.