How to increase the timeout of an Asp.net application MVC 4.5 framework

Question

I have an asp.net mvc 4.5 app that makes requests to a WCF service, the problem is that when the service takes more than 30 seconds the mvc cuts the connection to the service

I have already added the executionTimeout="300" and it still does not work.

A detail is that the local request works normally, but when deployed is when the error appears.

I also followed the steps of:

"Internet Information Services dialog box, expand local computer > Sites and right click Default Website and select Manage Website > Advance Settings. Expand Connection Limits, change the Time-out value"

"On the bottom panel, open Configuration Editor. In the top of Editor choose system.web/httpRuntime. Find option "executionTimeout" and set new value"

And I still can't increase the 30 seconds timeout.

Web.config:

<system.web>
    <httpRuntime targetFramework="4.5.1" executionTimeout="300"/>       
</system.web>