Dec 14, 2012
When a website’s ranking drop you must to send a proper reconsideration request to Google webmasters. When your site dropped ranking from spam issue then fixed quickly and send reconsideration request to recover ranking in Google.
Reconsideration request is that Google filled out form to inform Google that issue on your website have been fixed and your websites are now spam free. You can find the request form in webmaster tools and fill the form.
For more information on a proper Reconsideration request please see below video to know how to done proper reconsideration request by Matt cutts.