r3:

1) The model that you are working on was not delivered in the USA, and most of the people on this forum are in the US, so there is very little familiarity with the model.

2) Would you go into more explanation of this phrase: "when we load the accelerator". Is the car standing in neutral, and the throttle is suddenly opened? Is the car being driven, and the throttle opened suddenly? Is the load continuous, but then increased, as in climbing a hill? Etc.

3) Can you identify the make and model of the carburetor?