Yeh, sad I know, but with fuel around £6 a gallon my car rarely get to see the top side of 3000rpm unless I am on the motorway (and then only after accelerating slowly up to that).

What I am keen to find out is if there is any detailed information existsing for my car (04 plate 1.2 hatchback) that gives an idea of the optimum speed for economy (assuming a flat road and no head or tail wind), or would give an indication of the best gear to be in at given speeds. Not have an economy gauge on the dashboard I am left until I next fill up to find out how much fuel I have been using.

60 mph is pretty good for most cars - gives pretty low revs?

I can't say for sure, but 1.5k to 2.5k revs seems to work best for me, in town.

As accelerating uses fuel, not cruising, the balance is to either floor it, and get up to speed, then cruise.

OR, be gradual, and spend longer accelerating.

I can hit 50+ mpg in town, if I'm good with lights and it's quiet!

Motorways, I struggle to get mid 40... (cruising at 70.)

Remember to use hills, speed up going down, and slow as you go up.

This way you build up momentum when it's cheap (use gravity) and use it when it's expensive (against gravity.)

I'd still be interested in the gear / speed / fuel info though!

Might be time to experiment...

Probably different for a petrol, but I often find that if I'm crusing along, then sometimes it's actually best to drop down a cog if you're staying at a constant speed rather than sticking at a lower RPM. I'll see the onboard MPG go up by about 15 or 20 doing this.

I remember reading somewhere once that this was down to the ecu basically over-fuelling at lower revs to keep the torque up, so that the car could maintain momentum at lower RPMs.

Probably different for a petrol, but I often find that if I'm crusing along, then sometimes it's actually best to drop down a cog if you're staying at a constant speed rather than sticking at a lower RPM. I'll see the onboard MPG go up by about 15 or 20 doing this.

I remember reading somewhere once that this was down to the ecu basically over-fuelling at lower revs to keep the torque up, so that the car could maintain momentum at lower RPMs.

I would say that fact is correct.......by being in top gear at low revs at low speed is what we would think is saving fuel but its not as you might think.

I have been mpg watching for years with my tdi cars and to be honest it will drive you crazy.Just enjoy the ride and be safe :p

For really low fuel consumption I reccomed 56mph following a lorry with a 56mph speed limiter.

That speed/revs and no wind resistance means mega mpg. I could get over 70mpg on the VRS like that...

Well, I just had to see what was possible!

It was better than my 2011 Greenline.

I saw 77mpg on the trip in my vRS for a 65 mile jorney on M25/M1 recently - it may not be accurate but certainly put a smile on my face - the 50mph limits helped alot though!