Racer 38 you silly little boy..... 1 month, 1 day, 1 year! It don't matter. Pour it in and let her rip! I usually will dump some in the car as long as it already has fuel in it. If its less than 3 months old, I'll cut it with bout 2:1 of fresh fuel/oil vs. the old sh*t. And then I'll top of the tank by wizzing in it! nice pics of Llandow. Lookin' da bizness!