Following the success of the UltraLight Steel Auto Body (ULSAB) in 1997, the UltraLight Steel Auto Closure (ULSAC) Consortium representing steel producers from all over the world was founded. Porsche Engineering Services, Inc. (PES) was commissioned to conduct a concept study for the development of UltraLight Steel Auto Closure concept designs for all types of automotive closures that were structurally sound at affordable cost.
The Validation Phase began in November 1998. In spring 2000, the ULSAC DH Door Structures featuring stamped Door Outer Panels were built and tested for structural performance, dent resistance and oil canning. The tested doors show state-of-the-art structural performance compared to today's frameless door structures, and the mass reduction ranges from 22 to 42% compared to the normalized mass of benchmarked doors. In the Validation Phase, a cost model was developed and the cost to produce the ULSAC frameless door structure was calculated. The results of this cost estimation show that the ULSAC door can be manufactured in high-volume production with no cost penalty.