is it true...

sam83uk · 9 Feb 2007 at 13:08

that putting your foot down and getting though your gears asap to gain speed is more fuel efficient than accelerating lightly?

Gaygle · 9 Feb 2007 at 13:09

Not that i know of?

The total opposite AFAIK.

paradigm · 9 Feb 2007 at 13:11

Through personal research (i.e watching my MPG computer), I find that accelerating slowly/lightly is no more efficient than using moderate (normal) acceleration, then cruising. Its also less annoying/boring.

Hard acceleration kills my MPG though as it can see me as low as 5 MPG.

So I'd say the most efficient is a sweet spot between the two extremes.

dirtydog · 9 Feb 2007 at 13:11

sam83uk said:
that putting your foot down and getting though your gears asap to gain speed is more fuel efficient than accelerating lightly?

lol...

I suppose somebody might ask a more stupid question today... but I doubt it

monkeyspank · 9 Feb 2007 at 13:14

Fair question. I see where he's coming from... Getting up to speed quickly compared to a longer period of acceleration.

dirtydog · 9 Feb 2007 at 13:15

Does anyone here get better fuel economy when they thrash around, compared to when they drive gently? Erm... :rolleyes:

paradigm · 9 Feb 2007 at 13:16

dirtydog said:
Does anyone here get better fuel economy when they thrash around, compared to when they drive gently? Erm...

Don't be so pedantic, he didn't say thrash, although his question is worded badly.

Its not really a stupid question:

Scenario1: Slowly accelerate out of a junction, taking maybe 30 seconds or so to get to 60.

My car will do this at around a constant 20MPG, maybe less if there is an incline.

Scenario2: Accelerate with moderate briskness, taking maybe 10 seconds to get to 60, then cruise until reached the same distance as scenario1.

Thats 10 seconds of 15-18MPG, then cruising at 35+MPG.

I know for a fact that my overall average MPG is HIGHER with scenario2.

CSGAS · 9 Feb 2007 at 13:18

Well if you think about it - the energy wasted is always going to be (roughly) a fixed percentage of whatever you're putting in. You use more, you waste more.

dirtydog · 9 Feb 2007 at 13:18

Moderate briskness is not putting your foot down is it.

touch · 9 Feb 2007 at 13:19

paradigm said:
Hard acceleration kills my MPG though as it can see me as low as 5 MPG.

So I'd say the most efficient is a sweet spot between the two extremes.

Thats an instantaneous measurement tho. If you accelarate hard for 10 seconds to 60mph then cruise at that for 9mins 50, it may average out against slow accelaration for a full 10 mins.

...probably not, but it would be too much difference?

paradigm · 9 Feb 2007 at 13:20

touch said:
Thats an instantaneous measurement tho. If you accelarate hard for 10 seconds to 60mph then cruise at that for 9mins 50, it may average out against slow accelaration for a full 10 mins.

...probably not, but it would be too much difference?

It may be an instantaneous reading, but 1) I wouldn't be able to accelerate at 5MPG for 10 mins, i'd run out of road. 2) I have shown two examples using the average MPG readout from the trip comp.

Mr Jack · 9 Feb 2007 at 13:56

CSGAS said:
Well if you think about it - the energy wasted is always going to be (roughly) a fixed percentage of whatever you're putting in. You use more, you waste more.

That's not even remotely true. The % wastage varies wildly.

In answer to the OP, accelerating quickly (not hammering it, but getting on with it) is more fuel efficient providing you can then cruise for some time. You need to look ahead though, smacking it up to 70 if you then have to brake down to 40 will simply make matters worse. Basically every time you touch the brakes you waste a load of energy.

monkeyspank · 9 Feb 2007 at 14:10

dirtydog said:
Does anyone here get better fuel economy when they thrash around, compared to when they drive gently? Erm...

stop trolling mate, it just makes you look like a *****. he asked a question, maybe not worded perfectly but we know what he's getting at.

dirtydog · 9 Feb 2007 at 14:13

monkeyspank said:
stop trolling mate, it just makes you look like a *****. he asked a question, maybe not worded perfectly but we know what he's getting at.

"putting your foot down and getting though your gears asap" means driving at maximum acceleration, which means thrashing it. I'm sorry that you are offended that I called a spade a spade. The OP's question was stupid in the extreme I'm afraid.

How do you know that the OP meant something other than he said, out of interest?

monkeyspank · 9 Feb 2007 at 14:15

common sense

dirtydog · 9 Feb 2007 at 14:16

Heh

Something which the OP patently lacks or he wouldn't have made this thread!

hardc0re_tid · 9 Feb 2007 at 14:18

dirtydog said:
Does anyone here get better fuel economy when they thrash around, compared to when they drive gently? Erm...

in all honestly, i think i get the same if not more. my dad and i share a car, mine really, but he is a lightfoot on the accelerator but me, (i know ill sound like a boy racer/barry boy when i say this) but i take it to the red through each gear untill im at the correct speed for the area. car is a 1.1 saxo, tenner gets around 100 miles

there was a thing done on brainacs were richard hammond drove an ac cobra round an oval track 3 different times, with the same amount of petrol each time, with 3 different driving techniques, cant remember what the outcome was though

dirtydog · 9 Feb 2007 at 14:21

When I drive gently I get perhaps 35-40mpg, versus 25-30 driving hard. Full throttle burns through the juice in no time.

Actually even 25-30 is probably overstating it.

L0rdMike · 9 Feb 2007 at 14:22

Hard driving = 50miles to half a tank.

Easy driving = 150 to half a tank easily.

paradigm · 9 Feb 2007 at 14:29

dirtydog said:
Heh Something which the OP patently lacks or he wouldn't have made this thread!

Oh the ironing.