Originally Posted by mercmad6.3

The M180 started life in 1952 as the 220, in the ponton it was the 220a and then became the 220S with 7.6 compression ,different cam,single side plate on the block and twin carbs. Once the W111 came out ,the ponton engine was a still used but without sideplates and regular damper . By 1960 the m180 had the same carbs but a different cam and 8-1 compression heads were available to special order. Distributors changed a lot over the first 20 years from manual control of the timing for octane tuning to fully automatic for use with air con cars.
The good thing is that M127 engine uses a lot of parts like pistons and rods,crank that can be swapped in to make rebuilding easier and to use the better crank thrust bearing .
To improve performance on a m180 use the 230S 9.0-1 compression head with a cam marked 88 .
This cam has longer duration and deeper lift - more torque.
The chain wheel and tensioner need to be swapped of course.
The later twin carb manifolds marked 114 can be used with the weber conversion and W114 aircleaner for even more useable power and without a trade off for fuel consumption,unless you like gunning the car everywhere .
The greatest engine in the W111,actually W112 is the m189 3.0 liter. A real performance item.