Race Engine Forum UK

Hello,

I am the owner of a 124 Abarth in stock engine configuration. Carbs are the stock IDF 44.

Car runs well except for a flat spot off transition, every time I press the gas pedal. It happens when I drive it or when I rev it, at a stop. Whatever the engine speed, when I accelerate, there it chokes, shakes a bit and then picks-up properly. I have had that many times with Webers in other applications and never figured out what the cause would be? Wrong idle mixture?

Thanks

A blocked idle jet perhaps, pull them out carefully, 2 parts and O ring, clean them, they are always getting blocked.

Try that first, next the pump jet, does it produce a nice laminar jet when the throttle is opened? Check they are not dripping when the motor is idling.

GC