Achievements Xp limit

The default limit is 100Xp for all achievements in the game right? Is there any way to increase that limit? My game, PRO-R, http://nonoba.com/tedgaming/pro-r , has 30 achievements. Some of these achievements take 10+ hours to achieve and I wish to award players with more than 1Xp.

You're stuck with 100xp. I'd think about consolidating achievements.