Titles lenght with "Blog Posts"

I need to extend the length of the titles of the articles with the widget “Blog Posts”. In this moment the title is cut after the first half and it is followed by the three points (…). I need the full title to be visible. I succeeded in extending the extract of the article with the following code:

add_filter('avf_postgrid_excerpt_length','avia_change_postgrid_excerpt_length', 10, 1);
function avia_change_postgrid_excerpt_length($length)
{
   $length = 500;
   return $length;
}

. I need a similar thing, to be used for the title instead of the extract.