Whenever I watch Formula 1 on German TV, I notice that the commentators pronounce Caterham incorrectly, namely either as cat-er-ham [ˈkætəhæm], listen here, or as cater–ham [‘keɪtəhæm]. In both cases, the letter r is not pronounced, and the second part, –ham, is pronounced just like ham. The problem is that—as is often the case with place names—the pronunciation is far from obvious.
The team name Caterham is derived from the company name Caterham in Surrey (UK). According to Wikipedia, the town is pronounced as [ˈkeɪtrʊm], with cate– sounding just like the name Kate, the h completely silent, and the a in –ham pronounced as the -oo- in foot. Hence, the correct pronunciation only as two syllables, and the letter r is not silent. You can listen to the correct pronunciation here. Evidence for the fact that the people at Caterham indeed pronounce their team name in this way is given by the following video:, which itself got its name from the town
For the correct pronunciation of Porsche, see this post.