Default NEED HELP Rooting a ZTE WHIRL

I have tried to root this phone it does root but it is only temperorary it goes away after reboot.
I got busyinstalled in the /system/bin but no SU
The system is RO

I have tried this code to no avail
busybox mount-o remount,rw /dev/block/mmcblk0p18
cant be found in proc/mounts

busybox dd if=/sdcard/cwm.img of=/dev/block/mmcblk0p18
permmsion denied

I used framaroot and it said sucess then it said binary cant be installed any help would be great a thnk you ahead of time