Does anyone know if there is any difference between JCW and S engine blocks?

 

I believe the only difference is in the forged internals. Blocks are the same.

 

Yep, the block is the same, internals different.

Realoem is quite useful when you are not 100% sure whether parts are interchangeable. You can search for the part for your particular part, and then if you click on the part number it cross references all models compatible with that part. So that means I am pretty sure that the block itself is compatible on all of the following

https://www.realoem.com/bmw/enUS/par...&q=11110445412