I have a Spartan with a Mk1 2000 Vitesse engine, car runs great ,but even with normal driving only does 17 - 20mpg, the carb jets are adjusted fully up & I never need choke to start the car, so thinking it must be running rich, could having wrong needles in carb cause this, I have no idea which ones the are , but I think car was raced in the past , so wonder if they have been changed