If you're not a fanboy (and I am not suggesting you are), please find out more about the car and let us know. As you indicate, the weight of the HQ is 1800KG, which is rather heavy. To get a low drag time without Nitrous and fight the power-to-weight issue you're going to have to do a lot to the car.
Plus in comparing Japanese to "Aussie" cars you have to remember the different philosophies:
"Aussie": displacement is king
Jap: forced induction to create more power, or create power more efficiently using the same displacement for NA. Plus weight balance and handling are just as important as the KW figure. Examples:
RB26DETT: "206KW" using forced induction for 2.6L inline-6 engine
VQ35DE: "206KW" using naturally aspirated induction for a 3.5L V6 engine
"350" in HQ: "206KW" using naturally aspirated induction for a 5.7L V8 engine
The beauty of Japanese automotive engineering is not the on-paper figures however, but the quality of engineering, the efficiency, the reliability and the refinement.
The Japanese aren't stupid. Why not just expand the RB26 to an RB60DE and create mega power? Because that's not their aim.