20 years before the Celestiq, Cadillac was already trying to recapture their former glory as a leading luxury brand, and this was the car supposed to help it do so. The Cadillac Sixteen featured a 13.6-liter V16, developing 1000 PS using cylinder deactivation technology. The prototype actually ran, and was driven by media, including James May, who said it should be made. A toned-down production version with a V12 was rumored, but never materialized.