The overall effect of switching a static site to a blog platform should bump you up a good amount. You will want to submit the new blog to all the appropriate engines (technorati, digg, etc)
You should make an effort to submit new material to the site during the first sixty days, and keep a weekly article going onto it. If you don't plan on submitting fresh content, setup some RSS widgets to draw content from some good partner sites with relevant information. The RSS will not give you premium ranking, but it will give you more than leaving old content on the blog.

