Hi wasn't to sure where to post this but here goes

My current site is ranked in the top 20 for the word streetball on all major search engines. I built the site a few years back in Dreamweaver and I update it from my computer. What I want to do is recreate my site in wordpress but I'm worried my page will slip down the ranking. I've installed wordpress on my server and will eventually re-create the exact same design with the exact same content and then delete the existing index.html file. What problems will I have doing this as far as my google rank goes and what can I do to fix it?.

Sorry I wasn't sure which forum to post this in

If you change the URIs everything will go out of the indexes.

301 redirect the existing URIs to the equivalent new pages. Provided you are not changing hostnames it should recover in 4 to 6 weeks, though deeper pages may take several months.