XRAY - Model racing cars

i race on indoor carpet with my T3 2010 changed to geared rear diff last race car was good diff leaking a bit ( see other post ) but on the fourth heat car was getting to much grip on high speed corners and flipping the car never did this with rear ball diff anything i can change adjust to stop this happening ?

use less flex(more screws in top deck)
or
harder springs
or
wider car
or
thicker anti roll bar

but to make some changes you should see whats fliping first,front or rear
if front give more srews in top deck there
if rear give more srews in top deck there

All the tips above could help to avoid traction rolling. The most effective change to prevent your car from traction rolling is to set it wider in the rear than in the front. And here it's not too important to make it extensively wide. It only has to be wider in the rear than in the front. Don't forget to reset the camber and - depending on how much wider you want to set the trackwidth - you also might have to go one hole out on the upper shock mounting.

Did you check your rear suspention arms for free movement? Pinched suspension arms could lead to traction rolling, too. But in this case you would had some weird rear hand stability issues also. When you say it was not during the first three runs then maybe this had happened to your car or the track simply generated more traction during the event.