List of build.prop tweaks for SGY

To do this you need :
Root Explorer
then Open it, go to /system and find build.prop & edit it with Text Editor :

General Performance
debug.sf.hw=1
debug.performance.tuning=1
dalvik.vm.heapsize=48m *

Saves power
ro.ril.disable.power.collapse=1
pm.sleep_mode=2
windowsmgr.max_events_per_sec=60
wifi.supplicant_scan_interval=180

*If you don’t keep Wi-Fi active lowering the value below the default of 90 seems to make Wi-Fi connect faster after being turned on but will consume more power if turning Wi-Fi off has been forgotten when not in range of a known network.

Should smooth out disconnects and reconnects, saving battery.
ro.mot.eri.losalert.delay=1000

Raises quality of images
ro.media.enc.jpeg.quality=90
ro.media.dec.jpeg.memcap=8000000
ro.media.enc.hprof.vid.bps=8000000

Increased Media & Streaming Performance
media.stagefright.enable-player=true *
media.stagefright.enable-meta=true
media.stagefright.enable-scan=true
media.stagefright.enable-http=true
net.tcp.buffersize.default=4096,87380,256960,4096, 16384,256960 net.tcp.buffersize.wifi=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.umts=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.gprs=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.edge=4096,87380,256960,4096,163 84,256960

Disable error checking (Should speed things up a bit)
ro.kernel.android.checkjni=0
ro.kernel.checkjni=0

Use Jit (Dalvik just-in-time compiler)
dalvik.vm.execution-mode=int:jit

Enable Surface dithering (Improves image quality at the cost of performance)
persist.sys.use_dithering=1

Allow purging of assets (System can free more Ram when needed)
persist.sys.purgeable_assets=1

Disable animation for faster startup
debug.sf.nobootanimation=1

Wifi to scan less frequently
wifi.supplicant_scan_interval=180

Add these tweaks at the very bottom of the script.
Reboot to take effect. Don't forget to wipe cache ( user's belief )
* = edit existing line ( don't add new line ).
Sources :
-http://forum.xda-developers.com/showthread.php?t=771232
-http://forum.xda-developers.com/showthread.php?t=1685342

List of build.prop tweaks for SGY

To do this you need :
Root Explorer
then Open it, go to /system and find build.prop & edit it with Text Editor :

General Performance
debug.sf.hw=1
debug.performance.tuning=1
dalvik.vm.heapsize=48m *

Saves power
ro.ril.disable.power.collapse=1
pm.sleep_mode=2
windowsmgr.max_events_per_sec=60
wifi.supplicant_scan_interval=180

*If you don’t keep Wi-Fi active lowering the value below the default of 90 seems to make Wi-Fi connect faster after being turned on but will consume more power if turning Wi-Fi off has been forgotten when not in range of a known network.

Should smooth out disconnects and reconnects, saving battery.
ro.mot.eri.losalert.delay=1000

Raises quality of images
ro.media.enc.jpeg.quality=90
ro.media.dec.jpeg.memcap=8000000
ro.media.enc.hprof.vid.bps=8000000

Increased Media & Streaming Performance
media.stagefright.enable-player=true *
media.stagefright.enable-meta=true
media.stagefright.enable-scan=true
media.stagefright.enable-http=true
net.tcp.buffersize.default=4096,87380,256960,4096, 16384,256960 net.tcp.buffersize.wifi=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.umts=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.gprs=4096,87380,256960,4096,163 84,256960
net.tcp.buffersize.edge=4096,87380,256960,4096,163 84,256960

Disable error checking (Should speed things up a bit)
ro.kernel.android.checkjni=0
ro.kernel.checkjni=0

Use Jit (Dalvik just-in-time compiler)
dalvik.vm.execution-mode=int:jit

Enable Surface dithering (Improves image quality at the cost of performance)
persist.sys.use_dithering=1

Allow purging of assets (System can free more Ram when needed)
persist.sys.purgeable_assets=1

Disable animation for faster startup
debug.sf.nobootanimation=1

Wifi to scan less frequently
wifi.supplicant_scan_interval=180

Add these tweaks at the very bottom of the script.
Reboot to take effect. Don't forget to wipe cache ( user's belief )
* = edit existing line ( don't add new line ).
Sources :
-http://forum.xda-developers.com/showthread.php?t=771232
-http://forum.xda-developers.com/showthread.php?t=1685342