No need to search: You can find press releases from 2008 about engine control ECUs build around Infineon Tricore with 150 MHz:
http://www.tuneline.at/news/detail.asp?start=235 (sorry, in German)
The Audi V12 (diesel) is controlled by two 150 MHz processors operating as master-slave.
Everyone can be taught to sculpt: Michelangelo would have had to be taught how not to. So it is with the great programmers.