If I block the speaker, will it damage the drivers?

I have a pair of Paradigm 85F, pair of Totem Mini Sub and they are powered by Moon 340i Intrgrated Amp.

I found the mid bass is kind of overpowering and sounds blurry (this could be my room acoustic). But then I blocked the ports and immediately the mid sounds much better and I get clear high. The bass is still very nice from the pair of Totem.

Now, is this going to damage the drivers for long run? I just done it for like 5 songs and it sounds the way I like.

Blocking or "plugging" ports will not damage drivers. I say, "good for you" ; ports can be pretty bad. 
True about ports, especially since the mob continues to control a lot of the dock workers. Blockading the ports in that case just harms the consumer, but could possibly improve the sound of the waterfront.
By blocking the port, you increase mechanical resistance of the driver, so the speaker won't be as easy to drive, and consequently efficiency of the driver drops.  Nothing major unless you want to achieve a certain db point.