I know Stu has been very happy for me since I installed my new 455 over the Xmas break, especially when I tell him how good the fuel milage is.
Whilst, of course, I don't have a hemi in my pontiac, it still performs very well for such a heavy car, but the thing I've been surprised by is that with a steady right foot, I'm getting good economy from it.
A few weeks ago, I drove from my place (Wollongong) to Brookvale. Admitedly, I used the expressways and tollways, ie Hume Hwy, M7 and M2, but I was surprised to find that the car returned 21 mpg - on LPG. It only cost me $16 to make the trip (one way of course). I did try to drive the car as steadily as I could, but I did drive to the speed limit.
Also, last Saturday, when it was STINKING hot, I drove to Morisset, then Newcastle, then Maitland and back home. I had the A/C cranking the whole way and didn't really pay attention to driving the car smoothly. I was able to do the whole trip on 1 tank of fuel, with about 25 litres left (from 150 litres) in the tank.
Since Xmas, I've put 4,500 miles on. I'm pretty happy so far.
I would have to assume that Stu's Hemi is returning similar milage - or perhaps better, seeing as he has a much lighter car??