Extend animationtime

Hello. I have made one dissolving and exploding animated text, but I am not happy with the time settings . My animation stop in the middle of the explosion. I try to animate from fram 1 to frame 250. I think I suppose to do that in Cache but there is no frames 1 - 250
Take a look at my blendfile and tell me what missing. http://www.pasteall.org/blend/19713
Thanks in advance
Lurifax.