im running something similar to you (-35mm springs, c-one arbs, sp9000s and Wim'd) and don't find this a problem, but i am mostly driving in london. You must be driving pretty damn hard to get the back out - only really happens to me when i'm driving like an idot (not that i'm saying you are! lol) or on purpose -but i dont tend to do corners with the engine over 3.5k rpm so it wouldn't anyway I reckon.
How old are your tyres?