Several decades ago I went to an auto show in Chicago, and there was on display a mid engine Corvette based car with a blown big block Oldsmobile engine. Concept stuff that was designed, according to the display rep, to keep Ford & Chrysler from seriously considering a Corvette competitor for the street. It was claimed well over 550 HP at a time when 400 was a pile. I have not ever seen or heard one iota about that thing since, but the crowd around it was tough to navigate.
