abc

Hi all,

Been a while since we've had an MPG thread, so here's one with a difference. I'm told that Autoexpress (?last week) had an article about how to get better MPG by revving harder -- unlikely though that might sound!

Has anyone on here got it? If so, could you scan it and post it, please, or alternatively, give us the gist of what it said?

Thanks,

Andrew

andythejock01wrx

This idea I like !

Gear Head

iTrader: (2)

I havn't seen or read it myself, but the harder you rev, the more fuel you use. Nothing will ever change that, so I look foward to reading the article.

abc

Something to do with engine mapping, I think.

wrx-kris

labouring the engine uses more motion lotion

Brit_in_Japan

Haven't seen the article, but revving the engine higher does incur more pumping losses and there's more internal friction. However the engine may breathe better at certain speeds, and labouring an engine at low revs is not good for MPG either! Hope someone can scan it and post it up for scrutiny!

Gear Head

iTrader: (2)

Yes, I suppose you could map the ecu to run lean at high revs.........but then your engine would go bang!

stilover

Wasn't this on Top Gear years ago, or was it 5th Gear?

Anyway, Tiff did a study that concluded that using say 3 quarters throttle up to 60mph from stand still used less fuel than slowly accelerating (Quarter throttle) to get to 60mph,as you get to a steddy throttle travel sooner (constant 60mph) by hitting 60 sooner.

chippy17

exactly better to hit your cruising speed quicker as the old cimbustion engine is very economical once at cruising velocity

Gear Head

iTrader: (2)

There was a test on brainiac where Mr Hammond tested various types of driving in a caterham.
Out of 'driving like a granny', 'accelerate and coast' and 'driving like schumacher', the granny technique won hands down.
I always take a note of my mpg in every vehicle I drive/own. Have always found that low revs/throttle opening to be the most efficient.

mikepaul

At a constant speed below 2,500 rpm (e.g 60 mph), on a 120 mile run even a WRX can achive 35mpg easy!

Key to good fuel consumption
1) no hard breaking
2) excelerate slowly and reduce turbo boost
3)no hard cornering or sudden ants in pants motion
4) Turn off air-con and stereo
5) keep speed within the legal limits (drag factor)


It's always a good one to argue against the greens that a WRX can achieve a similar mpg to a people carrier TD!

But then again, most people on this forum seem to boast about how bad the fuel consumption is and seem intent to achieving the worst possible mpg

stilover

That's rubbish. Your talking cr@p.






STIlover
(I never get above 21mpg)

IRC450STI

I can get 290 to 300 miles on a full tank driving like a granny, is this good or normal, I drive a highly modified WRX with over 400BHP, im getting more from a full tank now than when it was standard...

wrx-kris

was one of your mods a 100L tank?

IRC450STI

If it is, fuel only costing me 50p ltr Cool i wonder if garage knows this, i get 105 mile up to 1st mark on gauge.

AllyJ

thats a commone outcome of remappings isnt it. I noticed my sti with a tsl 333 is now better mpg than the sti ppp for example.

IRC450STI

Dam thought i was getting cheep v-power, but when the foot gets heavy where has all my fuel gone i had a full tank 5 mins ago

abc

Agreed -- I managed nearly 37 mpg once. The look on people's faces when they criticise you for having a thirsty car and you tell them this is another reason why scoobies are such fun -- though not the principal one, I grant!

I think the Autoexpress article was arguing something like this -- hit the loud pedal hard when accelarating from standstill through the gears (though I guess important to keep off boost).

Anyone able to scan the article and post it, please?

andythejock01wrx

Luminous

iTrader: (3)

I have heard of research done like this before. It was concluded that brisk acceleration to your constant cruising speed was best for economy. I never heard the explanation as to why though.

StickyMicky

i have just binned the article yesterday

very interesting and looks like it will work, but not that practice for everyday driving

IIRC what they were saying is nail the throttle, the ecu should map the fueling perfect, back off compleatly and coast, useing no fuel, nail the throttle again and the ecu should map the fuel correctly, then back off the throttle so you kind of "seesaw" down the road

jasonius

iTrader: (1)

I really cannot believe some people have achieved >30mpg (36 lol..!) in their WRX's..!

How are these people checking their consumption I wonder..?

The best I've ever managed was 26mpg and average 22, which is 90% steady around town driving..!

Gear Head

iTrader: (2)

I managed 37mpg once in my MY99 UK Turbo a year ago. 50mph for 100miles, filled up before and after. It was also very, very hot.
Number of liters/4.545, then divide the mileage by the number of gallons used.

Jimpreza

I struggle to believe this aswell mate. I average 21 mpg in my wrx.

StickyMicky

i managed 282 miles to a full tank quite regular when travellng up from london to newcastle every month last year

think the classics have a 50 litre tank? around 10/11 gallons?

used to stop at the same service station every time, then fill up again and use the next full tank to blast home at warp factor 6

round the doors i usually get about 200 miles to the same tank