I am not responsible if anything goes wrong. You`re doing this at your own risk.
So, to get to the point, many users have reported a soft/hard brick. I recommend you trying this method, even thought the previous method worked for me every single time. That same method is quoted in the first comment, so if you want you can still try it. Install Jelly Bean E97510h from this link ( using KDZ updater )https://mega.co.nz/#!0gtWRABR!WSbEST...Y3UKMh3m4i7i14 Make sure you have an unlocked bootloader ( download app called "freegee" from the play store and unlock your bootloader using "mako" method ) and a recovery ( I recommend using CWM ):
After that install Paulicat, just to be safe https://drive.google.com/folderview?...kk&usp=sharing
( install it the same way as any other rom - wipe data/factory reset, wipe cache, dalvik cache, format system, install zip. wipe data/factory reset)
1. download Sling Rom 2.1
2. Download patch https://www.dropbox.com/s/7a3urpzvw4...lgviet.com.zip
3. Super su http://download.chainfire.eu/420/Sup...erSU-v1.99.zip
4. Put all three files on your sd card
5. Enter recovery >> Wipe data/factory reset >> Wipe cache >> Wipe dalvik cache >> go to mounts and storage and click "format system"
6. Install Sling Rom, then Patch and finally Super Su
7. Go back, once more wipe data/factory reset >> wipe cache >> and wipe dalvik cache
Reboot your phone and enjoy kit kat.. you dont need to flash 10H modem because I`ve already included it in the patch, and you dont need to unlock your bootloader. I`ve tested this method and it works 100%, if you cant get it to work than you`re doing something wrong.
If u have installed kit kat rom and have a weak signal then go to recovery, wipe cache and dalvik cache, install 10h modem >>>>https://www.dropbox.com/s/rzpnlwu1lo...-10h_modem.zip
Thanks @sunyakram for the rom links.