I've got a site which is a directory of races for my sport. There are about 1700 races each with its own page, so there are a lot of pages - except: there is no content regularly updated. Would adding a blog to my site help its ranking and/or traffic? Or should I create a separate blog and advertise my site on the blog?
Adding a blog certainly won't hurt, especially if you are diligent about adding fresh content. As for where to put the blog, if it is the directory you want to promote, I'd keep the blog on the site. Typically, a blog with regularly updated content is going to be more search engine friendly than a directory. Your blog may end up receiving more traffic and more links than your directory and it will be difficult to transfer that traffic to your directory if they are separate sites People are more inclined to follow links between pages on the same site than they are to click on advertisements.
Sure It will help you to bring more visitors. The main point is to post useful infromation. But if you want a blog to become popular under its own name, it is better then to register a new domain.