speedyxjs
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| posted on 24/6/09 at 10:36 AM |
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I hate tractors
I was well on target to break an average of 30 mpg on a 70 mile round jounnery (first half in rush hour) in my jag today when a tractor pulled out
infront of me on the way home 
When i got home the mpg had dropped to 27.5 
[Edited on 24-6-09 by speedyxjs]
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Jasongray5
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| posted on 24/6/09 at 10:38 AM |
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oi!! we put milk on your cerial, meat on your bbq and bread for your sarnies!
How hard can it be?
http://www.flickr.com/photos/33261515@N03/sets/72157611049241239/
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Mr Whippy
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| posted on 24/6/09 at 10:42 AM |
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how can the mpg drop if your going slower behind a tractor?
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speedyxjs
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| posted on 24/6/09 at 10:45 AM |
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quote:
Originally posted by Mr Whippy
how can the mpg drop if your going slower behind a tractor?
The tractor was doing 20 mph making the car drop to around 18 - 20 mpg
quote:
oi!! we put milk on your cerial, meat on your bbq and bread for your sarnies!
Yeah but this one wasnt carrying anything 
How long can i resist the temptation to drop a V8 in?
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MikeCapon
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| posted on 24/6/09 at 10:49 AM |
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I used to like tractors a lot.
Now I'm an ex tractor fan...
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speedyxjs
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| posted on 24/6/09 at 10:50 AM |
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quote:
Originally posted by MikeCapon
I used to like tractors a lot.
Now I'm an ex tractor fan...
Thats bad
How long can i resist the temptation to drop a V8 in?
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02GF74
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| posted on 24/6/09 at 11:05 AM |
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quote:
Originally posted by speedyxjs
quote:
Originally posted by Mr Whippy
how can the mpg drop if your going slower behind a tractor?
The tractor was doing 20 mph making the car drop to around 18 - 20 mpg
why is that? surely the resistance to forward motion, namely air resistance, is much less at lower speed so less petrol needed?
I've heard that car manufacturer's optimize engine parameters to get best mpg at the speeds for which the car mags/gov test the mpgs at
but still mpg should have gone up not down.
I am assuming you used the optimum gear so can anyone explain?
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Mr Whippy
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| posted on 24/6/09 at 11:10 AM |
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quote:
Originally posted by 02GF74
quote:
Originally posted by speedyxjs
quote:
Originally posted by Mr Whippy
how can the mpg drop if your going slower behind a tractor?
The tractor was doing 20 mph making the car drop to around 18 - 20 mpg
why is that? surely the resistance to forward motion, namely air resistance, is much less at lower speed so less petrol needed?
I've heard that car manufacturer's optimize engine parameters to get best mpg at the speeds for which the car mags/gov test the mpgs at
but still mpg should have gone up not down.
I am assuming you used the optimum gear so can anyone explain?
Clearly he sat there in second gear revving away trying to get past probably pounding the steering wheel and swearing a lot
my bike is brill for such occasions and it does 100mpg +
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blakep82
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| posted on 24/6/09 at 11:28 AM |
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my car gets better mpg at 40mph than it does at 30, same at 80 over 70.
________________________
IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083
don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
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matt_claydon
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| posted on 24/6/09 at 11:33 AM |
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The reason is that engines are not very efficient at low loads.
Air resistance goes up with the square of road speed, but engine efficiency also improves with increased speed and load (up to a point). If you drew a
graph you would find the lines cross somewhere and this would be the optimum speed to drive at.
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speedyxjs
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| posted on 24/6/09 at 11:58 AM |
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She is automatic (4 speed +overdrive). She doesnt change into 3rd until about 25.
How long can i resist the temptation to drop a V8 in?
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speedyxjs
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| posted on 24/6/09 at 11:58 AM |
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quote:
Originally posted by blakep82
my car gets better mpg at 40mph than it does at 30, same at 80 over 70.
Same as mine
How long can i resist the temptation to drop a V8 in?
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Mr Whippy
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| posted on 24/6/09 at 12:16 PM |
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hmm I suppose so, I think my bluebird being an auto also behaves the same, though I think the overdrive cuts in around 30mph if I back off on the
pedal. I'll have a check next time I use it 
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smart51
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| posted on 24/6/09 at 12:22 PM |
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quote:
Originally posted by speedyxjs
I was well on target to break an average of 30 mpg on a 70 mile round jounnery (first half in rush hour) in my jag today when a tractor pulled out
infront of me on the way home
When i got home the mpg had dropped to 27.5
My Peugeot sometimes drops to about 50 MPG but thats when I go faster not slower. 27.5 MPG? My BEC used to do better than that.
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speedyxjs
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| posted on 24/6/09 at 12:34 PM |
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quote:
Originally posted by smart51
quote:
Originally posted by speedyxjs
I was well on target to break an average of 30 mpg on a 70 mile round jounnery (first half in rush hour) in my jag today when a tractor pulled out
infront of me on the way home
When i got home the mpg had dropped to 27.5
My Peugeot sometimes drops to about 50 MPG but thats when I go faster not slower. 27.5 MPG? My BEC used to do better than that.
But was your bec a 3.2 litre, 2 ton beast?
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Mr Whippy
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| posted on 24/6/09 at 12:38 PM |
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ever considered converting it to run on autogas?
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speedyxjs
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| posted on 24/6/09 at 12:42 PM |
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quote:
Originally posted by Mr Whippy
ever considered converting it to run on autogas?
Yep but a) cant afford the conversion and b) how long will it be before government put the price of lpg to the same as petrol?
How long can i resist the temptation to drop a V8 in?
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Mr Whippy
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| posted on 24/6/09 at 12:57 PM |
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I fitted a kit to the bluebird that was just over £500, it would take less than a year for it to pay for itself on my car (45mpg) if I wasn't
using the little bike so much
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speedyxjs
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| posted on 24/6/09 at 01:01 PM |
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quote:
Originally posted by Mr Whippy
I fitted a kit to the bluebird that was just over £500, it would take less than a year for it to pay for itself on my car (45mpg) if I wasn't
using the little bike so much
Last time i looked, they were £1500 and i was reading horror stories about their fitment. How long do you think ot would take to pay for itself if i
only do 3000 per year?
How long can i resist the temptation to drop a V8 in?
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Benzine
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| posted on 24/6/09 at 06:36 PM |
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quote:
Originally posted by speedyxjs
how long will it be before government put the price of lpg to the same as petrol?
You've been saying that for years and it's still half
http://www.locostbuilders.co.uk/viewthread.php?tid=87251
[Edited on 24/6/09 by Benzine]
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Wheels244
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| posted on 24/6/09 at 06:38 PM |
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quote:
Originally posted by Jasongray5
oi!! we put milk on your cerial, meat on your bbq and bread for your sarnies!
and cr*p all over my car
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Benzine
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| posted on 24/6/09 at 06:53 PM |
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The workshop I rent is next to a couple of old chaps who spend all day playing around with vintage tractors and smoking cigars. This is what I plan to
do when I'm old
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speedyxjs
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| posted on 24/6/09 at 07:47 PM |
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quote:
Originally posted by Benzine
quote:
Originally posted by speedyxjs
how long will it be before government put the price of lpg to the same as petrol?
You've been saying that for years and it's still half
http://www.locostbuilders.co.uk/viewthread.php?tid=87251
[Edited on 24/6/09 by Benzine]
Hey... That was 14 months ago. I wouldnt call that years
I will probably look into it though now i know its much cheaper than i thought. Just got to save the £500
How long can i resist the temptation to drop a V8 in?
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