Do it. 12flat or faster, Right now
That wasn't $1000....
I suspect there is a lot more to that story, and definitely not a general rule of how they go
Obviously going by averages the Commodores are quicker at the drags, there will be examples of particularly quick Skylines and the same goes for Commodores. One of my mates has a Commodore which he did 12.9 in full street trim with stock exhaust etc, spent a few grand and has added another ~40% to his initial power figure - for all intents and purposes its still a fairly mildly modified car and I am absolutely certain its substantially quicker than my car in all respects when it had its GT3076R on it.
There is no replacement for displacement folks, your best bet for minimal outlay is get sticky tyres and a bit of NOS and get it tuned like that - 2RISMO style. 11s on stock turbo ftw.