SOLR Tracking is always asynchronous, you cannot switch to synchronous mode.
You can perform a query to SOLR in order to verify if a document has been indexed.
Thanks for your Answer.
That SOLR only works asynchronous is what i thought.
I can perform a query for new documents to check if they are indexed, but i also need to do it for updates on the document. But i guess there is no way to accomplish this with default Alfresco / SOLR behavior.