The Reventlow Scarab was made mostly by Troutman and Barnes, a couple of southern California street rod builders. The cars went out the first couple of seasons and just ate up the competition. Not bad for using mostly off-the-self parts. The next season they went up against the new mid-engine cars and never got truly competitive again.
Not only genuinely fast and maneuverable, but also one of the most beautiful sports-racers ever. It's been years since I heard, but Augie Pabst still had his as late as the early 90s.