I am creating a new MVC4 project, and research has lead me to believe that communicating from javascript to the server side is better achieved now through web API framework
In addition to setup the separate DLL for the Web.Api.
Just a Suggestion:
Create a a class Method to be called upon app_start
[assembly: WebActivatorEx.PostApplicationStartMethod(typeof(API.AppWebActivator),"Start")]
[assembly:WebActivatorEx.ApplicationShutdownMethod(typeof(API.AppWebActivator), "Shutdown")]
Register a web.api routes inside the Start Method
public static void Start() { GlobalConfiguration.Configure(WebApiConfig.Register); }
Reference the Project to the Web Project. to activate the Start Method.
Hope this helps.