That would work. But it might be easier to measure by placing the piston at top dead center (all the way up), fill with oil, then turn the crank until the piston is at bottom and re-fill, measuring how much you've added.Actually I am looking for a way to measure the actual displacement. For example: put a hose on the spark plug hole, put the piston all the way down, fill with oil and measure the amount of oil that is displaced by raising the piston to top.
You have a 12:1 compression 2.0? Presumably not an LNF engine!This gives the total cc of displacement and the head volume. Since we know the compression is about 12 to one we know that means that the total is 13/12 th of the 2.4 displacement and should total about 2600/4 CC which is 650.
If the engine is a 2.0 the number comes out 2166/4 = 542 CC.
The difference should be very easy to determine.