Economical driving?
20 March 2012, 10:11 AM
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Economical driving?
I know as a Impreza owner we didn’t buy them for fuel economy but was wandering what is the most fuel efficient way to drive them since I tent to try and keep it below 3K revs driving around town to keep off the boost but then if you think about power to weight ratio it’s using less power to move more weight without the turbo so is it actually using more petrol?
20 March 2012, 02:21 PM
#3
There is a bit of weight to this: As there is a sweet spot when building up speed. Full throttle is wastefull as the car enriches the fuel mixture, but not using enough throttle means you spend too long acelerating. I reckon it best not to spend too long accelarating, as best MPG is achived by maintaining a constant speed.
So I find it better to give some mild beans (i.e part throttle to 3-4K revs to get up to road speed then slot it in 5th or 6th once at my cruise speed. Block changing gears if need be if the car has a close ratio box, as you don't need to sequentially shift and use every gear with a close ratio gearbox, especially when going downhill.
I also avoid stopping at all costs. Needs some practice and good observation.
So I find it better to give some mild beans (i.e part throttle to 3-4K revs to get up to road speed then slot it in 5th or 6th once at my cruise speed. Block changing gears if need be if the car has a close ratio box, as you don't need to sequentially shift and use every gear with a close ratio gearbox, especially when going downhill.
I also avoid stopping at all costs. Needs some practice and good observation.
21 March 2012, 09:34 AM
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There is a bit of weight to this: As there is a sweet spot when building up speed. Full throttle is wastefull as the car enriches the fuel mixture, but not using enough throttle means you spend too long acelerating. I reckon it best not to spend too long accelarating, as best MPG is achived by maintaining a constant speed.
So I find it better to give some mild beans (i.e part throttle to 3-4K revs to get up to road speed then slot it in 5th or 6th once at my cruise speed. Block changing gears if need be if the car has a close ratio box, as you don't need to sequentially shift and use every gear with a close ratio gearbox, especially when going downhill.
I also avoid stopping at all costs. Needs some practice and good observation.
So I find it better to give some mild beans (i.e part throttle to 3-4K revs to get up to road speed then slot it in 5th or 6th once at my cruise speed. Block changing gears if need be if the car has a close ratio box, as you don't need to sequentially shift and use every gear with a close ratio gearbox, especially when going downhill.
I also avoid stopping at all costs. Needs some practice and good observation.
21 March 2012, 03:41 PM
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[QUOTE=MR2Mk1;10543832]I must admit it seems a bit guess work since I don’t have a boost gauge either just presumed since the wine of the turbo and acceleration doesn’t really start till 3K that was around the right area?
Yeah i work on the same 3k rule as you. That and the DV giving me an indication
Yeah i work on the same 3k rule as you. That and the DV giving me an indication
21 March 2012, 11:14 PM
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It's mainly driving style: Anticipating so that you vary your speed as little as possible. Acceleration sense so you're not burning fuel only to brake and turn it into heat moments later, and adopting a cruise speed and a high gear ASAP without labouring the engine. Basically driving as smoothly as possible. Droppping your cruising speed makes a massive difference too, but 60Mph is BORING.
Keeping the car maintained goes without saying - Faulty brakes, flat tyres and faulty O2 sensors all waste fuel.
I don't think you're ever going to see averages much above 30mpg in an impreza!
Keeping the car maintained goes without saying - Faulty brakes, flat tyres and faulty O2 sensors all waste fuel.
I don't think you're ever going to see averages much above 30mpg in an impreza!
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22 March 2012, 01:55 AM
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Bloody DANGEROUS as no servo help from the brakes. Also I believe it is ILLEGAL as it was used by truckers when being tailgated, switch off engine so no brake lights and then nail the brakes. Also you would loose power steering.
22 March 2012, 02:56 AM
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I know as a Impreza owner we didn’t buy them for fuel economy but was wandering what is the most fuel efficient way to drive them since I tent to try and keep it below 3K revs driving around town to keep off the boost but then if you think about power to weight ratio it’s using less power to move more weight without the turbo so is it actually using more petrol?
dumb topic, let this thread die.......... silly ****
22 March 2012, 07:29 AM
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It's mainly driving style: Anticipating so that you vary your speed as little as possible. Acceleration sense so you're not burning fuel only to brake and turn it into heat moments later, and adopting a cruise speed and a high gear ASAP without labouring the engine. Basically driving as smoothly as possible. Droppping your cruising speed makes a massive difference too, but 60Mph is BORING.
Keeping the car maintained goes without saying - Faulty brakes, flat tyres and faulty O2 sensors all waste fuel.
I don't think you're ever going to see averages much above 30mpg in an impreza!
Keeping the car maintained goes without saying - Faulty brakes, flat tyres and faulty O2 sensors all waste fuel.
I don't think you're ever going to see averages much above 30mpg in an impreza!
24 March 2012, 09:16 AM
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There is a technique called pulse and glide that the hypermilers use. It is between 10-20% more efficient than maintaining a constant speed on an A road or similar.
To try it out make sure you are on a clear road, as this is not recommended in heavy traffic! Gently accelerate to around 5-10mph above your ideal cruising speed, knock the car out of gear and allow the car to coast down to 5mph under your ideal speed and then repeat the process.
I have tried it on a number of occasions and it does work in terms of economy but it is a bit laborious and heavy on the clutch and gearbox since you are using it constantly. It works better if you combine it with hills for maximum effect.
Hope that helps!
To try it out make sure you are on a clear road, as this is not recommended in heavy traffic! Gently accelerate to around 5-10mph above your ideal cruising speed, knock the car out of gear and allow the car to coast down to 5mph under your ideal speed and then repeat the process.
I have tried it on a number of occasions and it does work in terms of economy but it is a bit laborious and heavy on the clutch and gearbox since you are using it constantly. It works better if you combine it with hills for maximum effect.
Hope that helps!
26 March 2012, 08:31 AM
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26 March 2012, 10:53 AM
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The Impreza is the replacement for my Mk1 since needed a bigger car but still wanted something fun to drive. Although the Mk1 was more fuel efficient and more fun to drive with the twitchy back end in the wet but that’s the charm of the MR2 you have to drive it rather than let it drive you.
The Mk1 MR2 taught you how to drive, properly. It was all about momentum, grip, chassis balance and keeping the engine on song.
Them Impreza just shakes it's head at you when you get a bit ham fisted and sorts it out for you. Not the best line through a corner? No matter, just boost your way out and you've not lost much, you'll still be going far too fast for the next one anyway!
I love them both, but they're entirely different, and I think the Imreza will have a lot of work to do yet to gain a similar place in my heart as my two Mk1's....
26 March 2012, 10:33 PM
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I remember getting my classic well out of shape flat in third gear once....
I simply braked and steered into the skid, leaving four huge black arcs around the corner...
They really do flatter us wheel monkeys
dunx
P.S. Only spun my STI once in the wet at Blyton, flat in third gear and calmly steered it straight as she turned through 180 degrees... my passenger thought I was showing off
I simply braked and steered into the skid, leaving four huge black arcs around the corner...
They really do flatter us wheel monkeys
dunx
P.S. Only spun my STI once in the wet at Blyton, flat in third gear and calmly steered it straight as she turned through 180 degrees... my passenger thought I was showing off
27 March 2012, 09:24 PM
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28 March 2012, 10:03 AM
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Absolutely. I can't really think of more "Chalk and Cheese" Drivers cars (within my realms of experience) than the MK1 MR2 and the Impreza.
The Mk1 MR2 taught you how to drive, properly. It was all about momentum, grip, chassis balance and keeping the engine on song.
Them Impreza just shakes it's head at you when you get a bit ham fisted and sorts it out for you. Not the best line through a corner? No matter, just boost your way out and you've not lost much, you'll still be going far too fast for the next one anyway!
I love them both, but they're entirely different, and I think the Imreza will have a lot of work to do yet to gain a similar place in my heart as my two Mk1's....
The Mk1 MR2 taught you how to drive, properly. It was all about momentum, grip, chassis balance and keeping the engine on song.
Them Impreza just shakes it's head at you when you get a bit ham fisted and sorts it out for you. Not the best line through a corner? No matter, just boost your way out and you've not lost much, you'll still be going far too fast for the next one anyway!
I love them both, but they're entirely different, and I think the Imreza will have a lot of work to do yet to gain a similar place in my heart as my two Mk1's....
.
24 April 2012, 03:19 PM
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An Update, just filled my scooby second time to full and calculated the fuel usage, my scooby does ( 29.37 MPG ) and no it is true, not fake. even i am surprised i was expecting something around 20 mpg. BTW, its like 60% town driving and 40% out of town. What is astounding is that i had toyota avensis se 1.8 petrol and that did 30 MPG go figure that one out, i cant.
29 April 2012, 08:44 AM
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Keep your tyres well inflated (harder tyres give better fuel economy but less grip!!), empty the boot, get your tracking checked, make sure you have a clean air filter & clean your MAF, use a fuel system cleaner and consider a good Teflon gearbox & engine oil additive. At worst all that will still cost under £100.
If it improves your MPG from 25mpg to 27.5mpg, and lets say you do 250 miles a week in your car, it will save you £335.40 per year in fuel!!
(and thats based on £1.45 per litre!!)
If it improves your MPG from 25mpg to 27.5mpg, and lets say you do 250 miles a week in your car, it will save you £335.40 per year in fuel!!
(and thats based on £1.45 per litre!!)
29 April 2012, 11:46 AM
#28
