Automatic headlights turning on when engine is started, exactly on 13.5 volts

With this circuit, the car headlights will automatically turn on when engine is started, or in other words, when input voltage in the circuit reaches 13.5 volts from the car battery/alternator, the circuit will activate a relay. With capacitor C1, the delay time is adjusted by wish, in example, lower capacitance will give shorter delay, higher capacitance will add more time to the delay.
Of course, this project is only simulation, use it, adjust it and test it on your responsibility. And enjoy :)

[@dedi1st169]

can use tl 072(dual opamp)?