ORIGINAL: N99JH
So, based on the way you can tell a Large from a small case - Fox is still making the large case engines. I went on their website and there are several?.
Fox still sells the small case version of the .40 too.
The small case .40 is only slightly larger than a .25, .28, .32, .35, .or 36 engine so it would work as a performance upgrade in some cases.
The .40's they show all are the small case engines whereas the .45 and .50 engines are the large case engines.