M117 distributor rotor
 

I got a 1972 280sel 4.5 and decided to refresh distributor parts on it. I bought them previously for my 1970 300sel 3.5. Everything looked the same except for the distributor rotor.

This one if for 3.5l and 4.5l up to engine 001421

http://i.imgur.com/f0Jk3.jpg


And this one is for 001422 and later 4.5l engine

http://i.imgur.com/JF5Tm.jpg


My engine is 8931, so I got to use the newer version. When I opened the distributor cap, I found out that my car has the older style rotor.
Does anyone know what's the difference between the rotors?

You bought a rev limiter rotor.
http://www.peachparts.com/shopforum/vintage-mercedes-forum/279306-rev-limiter-rotors.html?highlight=rev+limiter+rotor

Which one is the rev limiter rotor? First or second picture?
Which one I should use in the w108 4.5l? in euro w109 3.5l?

I don't think it makes much difference which ones you use unless you are in habit of over revving the engines. I think the most common one these days is the non- rev limiter type (first picture) and it is a lot cheaper.

Sounds like if the rev limiter is used, it is stamped 4.5 for 4.5L engine and presumably 3.5 for the 3.5L engine.

By the way, if anyone is looking for rev limiter rotors, I have two new 4.5L ones still in boxes that could be had cheap :)

bigger one is the rev limiter