Yesterday, I took a trip to Atlantic City and I reached speeds of about
70-80mph on the highway. The civic (2003) felt a little tense in my hands
when I tried pushing it to 80mph. I could feel the stick shift vibrating as
I passed 75 and into 80mph. I'm not sure if I'm having an issue here or
maybe the car needs more breaking in. By the way, I filled it with Mobil
Super; is that ok even though owner's manual recommends regular?

Dave