Which gas should I be using in my Civic??
 

I have a 99 Civic that I've been putting cheap gas in. My dad drove it the other day and he said that he can hear the difference in the engine already. What is the best gas that I can put in it? Will my engine "start to sound better" if I put good gas in it? What's the difference in octane #'s? I also heard NOT to put premium in it or it will clog up and mess things up more. Any advise would be appreciated! thanks!