A miniature XL bonnet Mystery (update: two 4 cylinders ?)

Radu Comsa has a keen eye for photos in small shops and markets. Even for small photos found in small shops. Last week he found this physical thumbnail measuring 10 x 20 mm! in a Bucharest antique shop. Due to the interesting and its amazing ultra long hood he made great efforts to get the very best scan you can get from a micro picture like this. At that point we didn't know it is a 'wellknown' car. We studied the unclear photo (clik main pic) and finally figured out the flag on the right wing reads 'Englischen Heirat'.

Armed with these two words the car was  quickly found on a much better photo. Earlier published on IMCDB and AutoPuzzles. We understand is is a Stoewer based Special but very little other is to be found, so we're still curious what can be found under the hood... Last minute before publishing we were lucky to find this clip from the 1934 movie Die englischen Heirat showing the car with open hood very clearly! It looks like a teamed up twin engine. Making a rough guess based on the visible HT leads we would say a twin ignition twin six.  Or is it 'only' the 100HP straight eight P20? Or...?