The LOGYKAL Classic Indycar Series are accepting signups for their 2018 season. This series uses the same free Dallara Indycar as the Undiecar Championship, but with longer events, often on paid tracks and with open setups. The races will be broadcast on Racespot TV.
Sign up and more information is available in the iRacing forum:
http://members.iracing.com/jforum/posts/list/3587319.page