When to filter search results with facets programmatically

Question

To group search results and display them in different blocks i want to filter them programmatically with facets.

I found a Solution, where the view is executed only with a new request object.

term = searchword
content = facet field

function theme_preprocess_views_view__search_view__page(&$vars) {
    $view = Drupal\views\Views::getView('search_view_groups');
    $view->setDisplay('block_groups');

    $filters = [
        'term' => $vars['view']->getRequest()->query->get('term'),
        'content' => ['bereich:80']
    ];

    $request = new Symfony\Component\HttpFoundation\Request($filters);
    $view->setRequest($request);
    $view->execute();

    dump($view->result);
    dump($view->getRequest());
}

The code works with params from the real request, but i can't change them in the hook. So i guess i use the wrong hook.

When should i run the filter? Which is the correct hook for that?

Setup:
Drupal: 8.3.5
facets: 1.x-dev
search_api: 1.3