Unfortunately not. This plugin allows you to change RMMZ's default speed for values 1 to 6 and the player's default value.
Acceleration is outside the scope of this plugin.
Edit: Actually, this plugin allows you to change RMMZ's default speed for any value, but you usually can only set values from 1 to 6 for events. You can bypass that for players and vehicles in this plugin's parameters, though very high or very low speeds may cause unexpected issues.