The Delay Activity causes the workflow to halt for a specified time period. This time is set using the TimeoutDuration property in hh:mm:ss format. The duration can also be initialized by specifying a InitializeTimeoutDuration handler. As usual an empty function will be provided in VSTA for editing when this property is named. Then example handler method is below:

public void delayActivity_InitializeTimeoutDuration( )
{
    this.Activities.delayActivity1.TimeoutDuration =
                           TimeSpan.FromSeconds( 60 - DateTime.Now.Second );
}