Hey guys, I'm finally turning my attention to getting the ute running 100% and I have a few questions that hopefully you can help me out with

I’m looking at replacing the lifters, because they seem to be not pumping up when the engine is above 1500rpm..
There is no ticking noise upon initial startup, nor is there any at idle.. but between 1500rpm and 3800rpm (<< I haven’t pushed it any further than that..) it just rattles and ticks off its head :/
Is there a possibility that by the lifters doing that, the cam may have been damaged? And if so, when I replace the cam and lifters, is there anything else I will need to do (mandatory stuff, not optional stuff like straight cut gears etc.)??

The timing seems to be out a fair bit, its down on power compared to before, and when you give it a fair bit of throttle, it loses its revvs and spits back out the carby :/
That is easily fixed with the timing being adjusted, but the main thing is its suffering from really bad pre-ignition (run on when key is turned off..)
It has always had it, but it is quite bad now, that bad infact I’ve had to stall it a few times to get it to turn off :/
Any ideas as to why and how to fix the pre-ignition??

I need to get these problems sorted soon, as I’m heading on a long trip, and want the car to be as reliable as possible Any help would be appreciated