Don't, if you don't want to speed run, as a tank you don't have to. You are the one that sets the pace of the duty, if rest of party doesn't like it, they can leave. If anyone tries to pull extra packs into your pull, let them tank it. This is a game, play it the way YOU enjoy it, and don't let others dictate how you play.
Thank you for the support! I have been literally leaving these groups lately because I don't even feel like dealing with it. I am not in a hurry, a little 30 min timer won't scrape me.

Nobody is forcing you to speed run, just don't be surprised if you end up getting kicked if the majority of the group wants to play their way and you don't comply.
I would be far from surprised if I get kicked for not going fast enough even though I am going at a really good pace. I am simply just not pulling as much as everyone else is or how much they are asking. I have seen people use the kick system for much less than this.