Factory specifications for this vehicle:

This 356 was brought in for tuning in preparation for the 2025 Mille Miglia. The engine stalled and lost power during acceleration.

Before the 356 was put on the test bench for measurements, the condition of the engine was checked:

1. Compression test: passed
2. Oil quality & fluid levels: engine oil was at the correct level, as was the coolant level.
3. Oil pressure: sufficient, between 3-5 bar.
4. Ignition configuration & timing: conventional system with contact points. The contact point opening was fine and the ignition was properly adjusted, but the resistance of the coil was very high, so we replaced the coil.

The aim of the adjustment was to improve the acceleration phase so that the driving characteristics of the 356 were restored. The main focus was immediately on adjusting the carburetors, as there were differences between the three carburetors.

After optimizing the carburetors, the car was tested on our own test bench.

1. During the first run, it became apparent that one of the carburetors was performing poorly during the transition phase. This caused the air-fuel ratio (AFR) to be much too lean, resulting in engine hesitation and poor performance in the 1300 to 2000 rpm range. Overall, the mixture was too lean during this phase.

2. The carburetors were disassembled and inspected. The idle jets were replaced with richer versions, identical for all three carburetors. The ignition timing was also adjusted.

3. After these modifications, the problems during acceleration disappeared and the 356 performed excellently.

We thoroughly enjoyed working on this 356 Speedster. The engine has been properly serviced in all key areas, resulting in a reliable setup.