and not knowing whether it is logistically and politically possible, the OP's plan for a circuit modification sounds good. It looks like there's room for very small modifications to that road to allow it to happen with minimal impact. You'd get a longer straight, a longer braking zone, we don't lose any particularly notable corners, it's not a huge change that would make the circuit overly long. I approve it.
With regards to space, yes it is possible. But to spend that amount of money to change an actual piece of road, rip up old asphalt to make it green and nice, lay new etc. etc. for one day with F1 race (yes I know they are driving three days, but the race is just one day, and it's only the race there are issues) is rather stupid.
However, I am not sure how large space they have behind the T1 runoff today. As there is a driving range right behind it.
Also IIRC, further down past T13 the road split up with trees, poles and grass in the middle. So it is just 2 car-widths there. Unless it is meant that Melbourne should remove even more green areas for one single race each year. In addition, what looks like a straight from the OP T13 towards todays second-to-last corner, is not a straight, it will be a right kink, then a left kink right in to todays T14, but on a road that I would guess is 55-60% of the width of the track they use today.
But then again. It is a (beautiful) public park which is a great place to hang out, walk around, not to mention use the dedicated cycling lines there to cycle around the park.
Then, from my walk around, you might also come across this
Edited by Myrvold, 25 March 2018 - 16:08.