My previous car, an Octavia vRS diesel was just under 5% optimistic when calculated over 40K miles. My Leon 1.4TSi (150) FR over 5K miles is currently less than 1% optimistic.
So far I've discovered it's a difficult beast to drive economically. Because of the ACT setup it seems to use more fuel cruising in a higher gear with a light foot, than it does in a lower gear with moderate revs and ACT activating. Hence my economy figures don't seem to change much either when I'm being light-footed :/I've just filled the tank after running a tank in Eco Mode and driving as economy friendly as I can. Most of my trips are very short, it's a second car, but it was the same type of journeys as before so a fair comparison of Eco Mode and sedate driving vs Sport Mode and using the revs a bit more.
Previous tanks average about 37-38 mpg.
This tank was 40 mpg.
I suspect most of that whole 2 mpg was due to driving style and Eco Mode does pretty much feck all. Sport Mode from now on then...
I'd like to see that.I'll try doing a tank-to-tank comparison too and report back.
It's apparently due to the inefficiency of petrol engines when supplying low torque. As I understand it, two cylinders supplying moderate pushing power require less fuel to be injected overall, than four cylinders sharing the same amount of work.I'd like to see that.
I'll be honest, I don't understand the ACT system. It's not like you're turning the engine into a three-cylinder one. It's still a four-cylinder when running on two so the rotating mass is still the same. I would have thought that moving the car a certain distance at a certain speed would require the same amount of fuel irrespective of how many cylinders that fuel is being burned in.
Yes - the total friction of the engine is the same, but by running on 2 cylinders at low load requirements those two cylinders are having to run at higher torque and are running more efficiently, converting more of the fuel into motion - most piston engines are most efficient around their maximum torque - the problem being at cruising speed they are nowhere near their maximum torque. All engines are basically over sized for cruising speeds to give us good acceleration and high top speeds.I'll be honest, I don't understand the ACT system. It's not like you're turning the engine into a three-cylinder one. It's still a four-cylinder when running on two so the rotating mass is still the same.
Yes - a car moving at certain speed would require a certain amount of power, but the amount of fuel required to make the required power varies with the efficiency of the engine.I would have thought that moving the car a certain distance at a certain speed would require the same amount of fuel irrespective of how many cylinders that fuel is being burned in.
There's an airline joke, where a 4 engine plane lost an engine, and pilot assured everyone, it was ok, we would just be 1 hour late, then the 2nd went, and the pilot as calm as ever, said, no worries, just 2 hrs late, then the 3rd went, and captain said the same thing, then the passenger commented, 'man, if the 4th engine goes, we would be up here forever....I'd still rather have 4 engines, in case one stops there's more chance of staying aloft?