[BLSTIC]

Ok, so I have a Toyota Echo. For those unfamiliar (...how...?) it's an 850kg (not willing to make it any lighter, I use everything installed in the car semi-regularly and I don't want to increase noise), reasonably aero (Cd 0.3) hatch with a moderate sized (1.3-1.5L) 4-valve engine that has sequential injection and variable inlet cam timing. My particular model is a 1.3L manual 3-door with no options except A/C, I even have manual steering, manual mirrors, and locking.

I live in a warm climate, with a typical max speed of around 60km/h, I think I average about 30km/h on my 8km commutes (traffic is fairly light).

I already run LRR tyres at 38psi and employ mild hypermiling techniques (driving with load, high gear fuel cut coasting, minimal braking). I have no desire to run kill switches, but I do key-off at long lights.

Currently I have a faulty thermostat and run the AC during the day so I'm at about 6.0-6.5l/100km around town. I would expect that to improve to 6l/100km regularly once the thermostat is replaced (car still warms up, but at night without a/c on when I get all the lights home it can take about 5-6km).

How much gain would you expect from the various eco-mods given that most of them are aero-based?