If you want more preformance and cheaper parts and repair costs install a 5 liter Ford engine in your car. You can easily get 50% more hp and 50% less cost this way. I have a Euro 280 slc that had a 5 lit. Ford installed in it. I bought it as a parts car because the installation was not well done but it did show me that the engine fit into the car with a lot of room to spare. The important thing in this conversion, unlike trying to get a 350 sbc in this car, is that the tramsmission goes in with room to spare. The Ford is a front sump engine which also helps. I am hoping to make this swap in my 1977 450slc.

In you are just starting out with MBs you had better prepare youself for some parts counter sticker shock. The price of things like the fuel pump and the fuel distribution unit will stop your heart.