Volumetric Efficiency

Hey, so Ive got two questions..

1. intake restrictions, exhaust restrictions, and cam design all will prevent the cylinders from being completely filled during the intake stroke, is there a way to figure out which one, or ones, of these things is the case for restricting airflow on a particular motor we are working on?

2. when calculating the volume of a cylinder, we are only calculating the actual cylinder, for the stroke we are calculating for in our v=3.14xr(squared)xstroke stops at the top of the engine block right? What about the space in the combustion chamber?

In terms of restrictions to VE, all of the listed aspects will add up to reduce or limit the airflow through the engine. You can measure certain restrictions such as those imposed by the airbox, air filter or intake system by measuring the pressure drop through these components. Likewise you could measure the exhaust system back pressure to get an indication of how restrictive it is. Ultimately though working out how to get the best improvement from a particular engine is all about testing on the dyno. Unfortunately this can also be a time consuming and expensive process.

When we are calculating the engine volume, we're actually calculating the swept volume or the volume a cylinder displaces during the engine cycle. The clearance volume (volume of the combustion chamber/head gasket thickness/piston dish volume) comes into play when we are calculating compression ratio.