I think most compounds you tend to start to adapt after a certain period of time. What do you feel is different than, say, week 4? Winstrol (winny) isn't much of a "pass" drug, but I was gonna say that if you weren't seeing as much size gains, alot of time it is because you have gotten to a heavier weight over those 8 weeks, therefore your maintenance cals are higher, and therefore you need to eat even more to have a surplus and to grow more.