See main article Mercedes-Benz SSK 
While the S and SS were successful in races for sheer speed, they did not perform as well in terms of turning ability.
So in late 1928, a new version of the S-Series was created to compete in hill climbs.
This model, called the SSK, which stands for Super Sport Kurz (German for 'Super Sport Short’), had a wheel base shortened to 2950 mm, and used the improved engine from the SS but kept the lower radiator from the base model S. Its improved handling together with a top speed of 119 mph made it the most fearsome racecar of its day.
See main article Mercedes-Benz SSK 
While the S and SS were successful in races for sheer speed, they did not perform as well in terms of turning ability. So in late 1928, a new version of the S-Series was created to compete in hill climbs. This model, called the SSK, which stands for Super Sport Kurz (German for 'Super Sport Short’), had a wheel base shortened to 2950 mm, and used the improved engine from the SS but kept the lower radiator from the base model S. Its improved handling together with a top speed of 119 mph made it the most fearsome racecar of its day.
Mercedes-Benz S-Series