I don't like autos

[landspeed]

Just to say, my current car is an auto, with the following specs:

2.0i multipoint, 8 valve.

4 speed (3+overdrive) gearbox, with lockup only on overdrive, only at 45mph+

And, I have found that, if I use the SuperMID to try different techniques, going slower (with engine -on and engine off coasting) is about the same as racing hard from the lights, going faster, and so on, on the same daily commute! I just can't make my MPG go any higher.

What I think is happening is this:

When cruising at low RPMs, the torque convertor slip becomes a greater percentage of total RPMs, so at low RPMs, efficiency DROPS due to the torque convertor.

At high RPMs, the engine is less efficient... but the torque convertor is 'wasting' less of the energy.

Therefore it makes no difference what RPMs you are at because the torque convertor efficiency (better when higher RPMs) and the engine efficiencies (worse when higher RPMs) cancel each other out.

Also, as you accelerate with more throttle, you get higher engine efficiency. However, when you accelerate with more throttle, the torque convertor slips more as well. Again these seem to cancel each-other out.

So overall, My range of fuel usage has been '1.450 litres' (on an uncalibrated SuperMID) for the best journey, and 1.550 litres (on the same SuperMID) for the worst journey. I have managed to get 1.650 litres with lots of traffic but that is another matter.

Any ideas on how to get past this block? I have a long drive at 45+mph coming soon so I'm hoping that will be good, but town driving in an Auto is a joke (this car is basically mechanically the same as my last Bluebird, except it is an auto). Yet it gets half the MPG!