It's the same for me too. Many people hate on nofap but it truly has been the absolute cure for me. This is just anecdotal, but If I consistently don't masturbate for >7 days my stutter pretty much becomes non-existent. I strongly encourage my fellow stutterers here to try nofap and no porn for at least a week. If your speach doesn't improve then you can go on your merry fapping ways.