Hi there,
The specs you mentioned above should work fairly well with UE4, here are the minimum required specs shown in the FAQ:
Desktop PC or Mac
Windows 7 64-bit or Mac OS X 10.9.2 or later
Quad-core Intel or AMD processor, 2.5 GHz or faster
NVIDIA GeForce 470 GTX or AMD Radeon 6870 HD series card or higher
8 GB RAM
So you shouldn’t have any problems running the editor. You may want to upgrade your video card at a later date to get a higher FPS, but what you have now should work quite well.
Hope that helps! 