In the LA/Orange County/San Deigo area, the cops do not enforce the freeway speed limits, simply because it is more dangerous to pull someone off a fast moving freeway ticket them, and have them pull back into traffic, than it is to let them be. so, for all intents an purposes have no speed limit on a freeway, a'la the Autobaun [sic].
there are spped limits in residential and school zones however, but with a school zone it is only if 2 or more children are nearby.