What does it mean if, when I want to speed up in traffic to change lanes or pass, I push the gas pedal hard but the engine just races with no increase in road speed? The only way I can accelerate is to slowly give it more gas and gradually speed up. This happens both in town at 25 mph or on the highway at 50 or 65. I also have little power when coming off a stop sign, until it gets into 3rd gear.
I've got a 350 V-8 with auto TH350 trans, 4-bbl carb. No engine modifications.

