"That's obviously not the factory engine, what is it?"
1955cc motor (76 x 90.5), Weber 32/36 DFEV progressive carb, dual-port heads, Engle 100 cam, dog-house cooler. Built as a mileage motor, 85+HP. KCR transaxle, double spider gears. Front disc brakes, rear Type 3 drum brakes. 0-60 mph in about 9 seconds, cruises all day at 75 and tops out at just over 100 mph. As reliable as a stock 1600cc VW, but with the performance equal to or exceeding a Porsche 912. Competed/completed 2013 Peking to Paris Rally and 2017 Great Race.
More here:
https://www.facebook.com/PekingToParis2013LittleRed/