In your example, the 46 represents .46 of a cubic inch.

By the same token, if you had an OS 120, it would be 1.2 cubic inches, but....

If a guy was talking about a BME 44, it wouldn't be .44 0f a cubic inch, but 44cc's, and if a guy had a ZDZ 120, it wouldn't be 1.2 cubic inches, but 120cc's.

So that is the short version...just remember that there are roughly 16cc's to the cubic inch, so .46 X 16=7.36cc's...and you might see a guy with a K&B 7.5 ducted fan engine..it is a .45 cubic inch, not 7.5 cubic inches...that would be a 120cc

(all conversions are rough figures!)

Happy to confuse you!