For fake shine/specular reflection, you kind of need light vector and camera vector, then you make dot product of them (but that is where i am lost, so i may be wrong). Bigger the dot more shine the pixel should be.
I am working on material like that. Ie. material with fake light, using normal maps for shadows, and using camera+normal map for specular shine.
There is also second way for doing it: with ambient cubemap. It works well, but requires texture. Because I am doing it for mobile i rather find pure vector solution.
Ps. try to dot camera vector with this fake light material from picture above. Or google for UDK materials that have sun reflection, googling for this in UE4 is futile as almost every link leads to new features.
Here is such material, group D does that shine: Hourences.com – Tutorials – UE3 Water Outdoors
Idea is same, but needs to be translated to ue4 and use blueprints. Something like this should do specular shine.