An excavation system is disclosed for a machine having a work tool. The excavation system may have a speed sensor to detect a travel speed of the machine and a load sensor to detect loading of the work tool. The excavation system may also have a controller configured to detect engagement of the work tool with a material pile based on at least one of the first signal and the second signal. The controller may also be configured to select at least one tilt control parameter value for the work tool and operate the work tool based on the selected tilt control parameter value to load the work tool with an amount of material. The controller may be configured to determine whether the amount of material exceeds a target amount and to cause the machine to withdraw from the material pile when the amount exceeds the target amount.