Hello Glen
AFAIK / going from distant memory...
...the 175kW engines were the standard/base model with the E7TE(?) heads
Higher rated engines were largely Heads/Throttlebody and later cam
this link shows the engine combos (I think I recognise one of my brother's apprentice's name in there...)
aufalcon.com - Home of the Ford AU Falcon Club | Australian Ford Falcon AU Series Club for Members
The machine ported GT40P heads on the 220kW are the same as the 250kW I think
A while ago I got a copy of the tech specs/service manual on the 250kW motor (cant find atm)
From memory the rocker ratio is 1.7:1 rather than the usual 1.6:1 and The cam lift at valve comes in at about the same as the ford E303 cam
LoBelly