Date registered: Oct 2008
Vehicle: 1959 190, 1961 190SL, 1967 250SE 4Spd, 1968 220D 4spd
Mentioned: 1 Post(s)
Quoted: 5 Post(s)
I also have a '61 190SL.
The original air filter is terrible, and grossly inefficient. It was made of some type of animal hair-type fibers, and bathed in oil. Particles in the air stick to the oil, and purified air passes through into the plenum. Nice for the 1950s, but pointless in the world of good quality paper filters.
The popular modification to do is to remove the screen section, and cut a piece of round modern-style filter to fit inside the container. When done correctly, there is nothing aesthetically to suggest that anything unoriginal is going on, which was key for me. There is plenty of discussion on this topic on the 190sl owners group forums.