Accurate combustion chamber measurements
Compression ratio is important in engine performance and durability. Higher compression ratios mean better performance and efficiency, but too high means reduced engine life.
Former methods of measuring the assembled chamber required safety margins of .5cc or more, meaning the engine never had its optimum ratio, and the ratios varied over the four cylinders. Now you can measure the assembled chamber to an accuracy as good as you can read on the burette. Your 9.25:1 cylinder does not have to end up at 8.9:1.