It all comes down to the fuel being used, the fuel pressure setting and the air:fuel ratio. It is impossible to make blanket statements like the one above.
Think about it for a minute. What power would those injectors support at 60psi base fuel pressure but running Methanol? How about oxygenated leaded race fuel? PULP?
It might be a good general guide to say that 1000cc injectors could support 1000 engine horsepower at 45psi base pressure and 12.5:1 but to make claims about any particular setup's capabilities without knowing the fuel type used, the pressure, the air:fuel's and the injector size is foolhardy at best.
Here we know that it was running 1000cc injectors, I've had a 'stab' that it's running Sunoco MaxNOS (as it's the new hotness;)) but we don't know the fuel pressure the reg was set to or the AFR's tuned to. Let's say 13:1 and 65-70psi should be enough.
Possible but more likely that the 1002hp is a great indication of flywheel horsepower.
The terminal speed on the timeslip (if this car ever makes a full noise pass down the quarter) and the race weight of the car will give a better, more 'real-world' comparison and idea of the power the thing is making.
***EDIT***
I had to laugh at the genius of an engineer above too!