Someone posted earlier today that the 51 bus came with a 36hp 1200
cc engine as opposed to the 25hp 1100 cc engine of the 50 bus. I have
some information contrary to that from VW....via Lindsay Porter's
VW Beetle & Transporter...

" 1950 - The first VW Transporter was produced in February. Mass production
started on march 8th with ten vehicles per day. Engine: four cylinder
air colled boxer engine, swept volume 1131 ccm, 25 hp at 3300 rpm...."

"1954/55 - The swept volume of the four cylinder engine was increased to
1192 ccm by a larger cylinder bore (75 to 77 mm bore). Increase in output 
from 25 to 30 hp at 3400 rpm."

Ric