Car doesn’t make 120 anymore

Hello ! My car (Lada Samara) can hardly make it over a mountain. If you start with Choke he does not bring any performance. At about 80 degrees it is better then. He manages with 3 people on the highway just 120. Changed were: petrol hoses, bezin filter, air filter, spark plugs, ignition distributor and fingers. What could it be about ? Would be grateful about every answer.