A VS V8? Get with the times my friend. The car was probably used as a paddock basher....
If anything Ford actually under quote their power figures. Don't think that just because it's Australian delivered doesn't mean it can't punch out the numbers.
Take a look at www.fordxr6turbo.com and you'll see what I mena. 280rwkw is nothing and costs bugger all for these cars. No mucking around with bigger turbos, intercoolers, ECU's, cams blah blah blah $$$$.
I have just finished flashing my dad's XR6t with an 8psi map and let me tell you it pulls like a freight train. Might try the 10psi map with decent fuel in it very soon. All for $1200.
The R34 might look better but it certainly does not match the power of the XR6.