2 mpg

(09-12-2011 12:26am)PhilSkill Wrote:  Full 4wd, a couple of tonnes and brick like shape... generally its what youd expect really, although I do hope it will improve as the engine loosens up. depends on your driving style and how much accel/decel you do, it looks pretty economical on long fast roads, but town driving stop/go certainly drinks it!

Are you refering to your Sd4 or the Si4 in general?

Either really same facts apply to both! But I only have experience of the SD4! which is at least in the 30's rather than the 20's... SD4 barely gets above 2000rpm and always quickly into 4th/5th/6th if you drive it carefully as so much torque low down, I imagine the petrol will need to rev higher to get the torque to accelerate and so thats where the mpg disappears to.

I have a very heavy right foot and most of what I have been doing so far is hooning around my favourite roads of the Cotswolds and of course there's lots of acceleration and braking.

When I get more into normal use such as motorways up to the Lake District or in to London, it will doubtless be better and on a motorway cruise at 75 - 80 I'm sure will be fine. However, extract the performance and the consumption increases significantly.

I'll be happy if I achieve 25 mpg as a long term average.

I put my instantaneous display on tonight and it showed 2mpg also with foot planted at low speed, but the low speed is the dominant factor, because at 10mph with throttles wide open the instant calculation is basing itself that if the car stayed at 10 mph to achieve 2 miles would take ~10 mins, 10 mins with the throttles open will guzzle a small tankers worth! the reality is the speed increases and this factor becomes less dominant, and also you back off and suddenly you see 99mpg as no fuel is being injected at all!

all this averages out to your real life mpg.

So lots of slow stop start gives a poor mpg, lots of high speed cruising give much better figures!