How do I increase the timout when initializing Solarium Client in PHP?

Question

I am using Solarium client 3.8.1, and I tried:

    $config = array(
        'endpoint' => array(
            'localhost' => array(
                'host' => $host,
                'port'     => $port,
                'path'     => $solrPath
            )
        )
    );
    $solariumClient = new Solarium\Client($config);
    $solariumClient->setAdapter(new Solarium\Core\Client\Adapter\Curl(array('timeout' => 300)));

However, when indexing after such an initialization, the timeout remains at 5 seconds. Similar, much older, questions posted either provide broken links are incomplete code examples.