Calling a Simhub function inside a Plugin

I'm trying to write a plugin to calculate some information, and one of then is the time gap between cars.
I know Simhub has the function "drivergaptoplayer(raceposition)", but how can I call this function inside the plugin?
To see the speed from my car I can use "pluginManager.GetPropertyValue("SpeedKmh")". Is there something similar to this approach for functions as we have for properties?