I have gotten a eb v8 a little while ago which it was running rough so i changed a few thing, oil, oil filter, fuel pump ( faulty ), spark plugs, ignition leads, alternator and new battery.

I had it running but still a bit rough better when the new oil went in, but ive let it sit as it was summer and too bloody hot to do a lot to it, Recently i've decided to crank it again but it refuses to start, i thought the fuel pump was gone again so i've replaced it again, there's BP 98 fresh fuel recently put in it, I got it started barely it runs rough and i needed to keep pumping the accelerator pedal to keep it going but it was back firing alot and still running rough.

What could it possibly be? ecu, timing?

Hopefully timing, check that first and see how it goes, also check to see if the injectors are working properly.

Carefully touch each header to see if there all warm/hot

first thing that comes to mind is your maf is stuffed..

I assume you changed the fuel filter when you changed the pump?
Do a self test.