Yeoh Bro, as said many times,
JB ROM needs
JB boot.img to boot up so unless your A8 has a similar case as A110 then you are indeed lucky to get it booted up... :fingers-crossed:
While many says A8 is a MT6517, there are two method to check,
adb shell ->
cat /proc/cpu_info, the other one is to reboot into
Factory Mode & check out the
Version to see if its indeed MT6517 or MT6577... :laugh: Refer to
here for more info... :fingers-crossed:
Just copy modem.img over if not whole /system/etc/firmware to ported ROM... :fingers-crossed:
As said, you never try, you'll never know, just as
boybakat here, he ported MT6575 ROM to his MT6515 SoC... :good: