I just bought a use 16in Dunlop tire for $30.00 and when I got home, I see that, the tire had some crackling around the side of the tire. The thread on it has tons of life left, just the minor crack around the sided of the tire worries me.

Well the tire be alright for Drag Racing, and Long Trip meaning 8 hours drive...??

 

That kind of cracking is what most people refer to as "dry rot". It means the rubber has lost it's elasticity - generally due to age. Ozone and UV accelerate the process. I would not run the tire, for safety's sake.