While production of the 220SE began in April of 1958, the model would not come to market until September, and even then the Mercedes regular production lines would not get underway until October.
In most respects the 220SE was identical to the Mercedes 220S
, the only change being the introduction of fuel injection.
Instead of using the twin Solex downdraft carburetors fitted to the 220S, the Mercedes engineers instead fitted a Bosch two-plunger injection pump, which in-turn provided an instant increase in power and torque, making the SE a far more tractable car. The horses on tap jumped from 112 SAE to 134 SAE.
The new manifold injection system was not cheap to manufacture, it adding approximately 2000 DM to the cost of the car.
But those lucky enough to get their hands on one could immediately tell the difference the Fuel Injection system made. There was 18% more power, 5% greater torque, and an estimated fuel consumption reduction of 8%.
The system was far from being simple, the air collection chamber having six intake pipes feeding the air into individual ports, just ahead of the junction between the manifold and cylinder head.
A calibrated jet was used for each individual cylinder, the fuel being fed by the two plunger pumps operating at engine speed. Injection was also controlled by temperature and barometric pressure.
This is an important point to note, as the system was vastly different from the EFI systems of today. It was not a direct injection system, rather a manifold injection system.