I'm looking to converting my son's 6 rib pulleys to 8 rib. I would like to do this as cost effectively as possible since we are already at $6600 on engine rebuild. I know that Thumper makes a nice looking tensioner that should hold up to the Vortech pretty well. Vortech also offers a complete 8 rib set up but they seemed way to high. If any of you could share some insight on the most cost effective way to do this I would really appreciate it.