OK I seriously don't know much about Marketting Techniques, so I am really interested to know, what is the best way of getting real members to a street racing forum. Any help in this regard would be appreciated.
Find out similar forums and blogs. Then start posting/commenting there. Contests work well sometimes.
do you have any quality street racing content on the forums? no reason to show them, if there isn't anything to look at
If it is a new forum, first try to add few content to the site.. Do it daily and the forum will be full with posts within 30 days..and you'll get a decent amount of traffic from the search engines...that'll move your forum. Google luck.