Exclude a type of content from drupal search results, + limit to 8

drupal_exclude_node_type_search.php

/**
 * Excludes node type "foo" from search results
 * 
 * @param object $query
 */
function mymodule_query_alter(&$query) {
  $is_search = FALSE;
  foreach ($query->getTables() as $table) {
    if ($table['table'] == 'search_index') {
      $is_search = TRUE;
    }
  }

  if ($is_search) {
    $query->condition('n.type', 'foo', '<>')
    ->range(0,8);
  }
}