Default Real Reacing 3 Perfomance on Acer 511

First Sorry for my Bad English

I have a Problem with my Acer 511 Stock Rom 4.1.2 root

I play the Game Real Racing 3 and the Performance ist not good. The Game Lag, no smooth Scrolling.

The Graphic is set to Low by Default.

I have test some Tweaks. Set LCD Density lower 213. Overclock Tegra 3. Disable Vsync, nothing Help.

Has anybody this problem and a Tipp to resolve?

GT Racing 2 Run Perfect with High Details.