Porsche: Pronounciation of Porsche, correct pronounciation, e sound

Question
My son and I disagree on the pronounciation of the name of this car.  I say "Por-ssh" and he says Por-sch-a.

Please tell me if either of the above is correct and, if not, what is the correct pronounciation?

Thank you

Answer
Well, both are somewhat correct. It's all a matter of which one you think is better.  Por-sch-a is the actual original 100% German way to say Porsche.  But the English language does not allow for the "e" sound to create an "a" sound unless it has a hyphen like some spanish charecters (e').  So the gramatically correct English version is Por-ssh while the original German translation is in fact Por-sch-a.  I prefer Por-ssh because it's easier to say but on occasion I'll say Por-sh-a.