WOW 27mpg

  • Thread starter Thread starter mossypossy
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mossypossy said:
Max torque in a 2.8 diesel such as mine is as astonishingly low 1800rpm
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Max Torque does not equate to Max Economy.

You should run at around 2,000 rpm when in 5th gear. This will give a speed of around 56 mph if you have the 'long' 5th gear. It depends if you have the old 5 speed box or the newer type. Which way do you select reverse? If it is toward you and down, you have the old box, if it is away from you and up, you have the newer one.

BTW, don't expect 27 mpg all the time. My 5 ton Burstner with overcab and 2.8 JTD averaged 22 and a bit mpg over 5 years of ownership. You could squeeze a little more with better aerodynamics but the 2.8iTD was slightly thirstier than the JTD.
 
maingate said:
You should run at around 2,000 rpm when in 5th gear. This will give a speed of around 56 mph if you have the 'long' 5th gear. It depends if you have the old 5 speed box or the newer type. Which way do you select reverse? If it is toward you and down, you have the old box, if it is away from you and up, you have the newer one.

BTW, don't expect 27 mpg all the time. My 5 ton Burstner with overcab and 2.8 JTD averaged 22 and a bit mpg over 5 years of ownership. You could squeeze a little more with better aerodynamics but the 2.8iTD was slightly thirstier than the JTD.
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I tend to stick around 55mph because I find it relaxing and very good for economy, it is a lot easier and less gear changes since I bought that tuning box from you and hill climbing has been a revelation so thank you, it was everything you said it was
 
Our 2001 Kontiki with a 2.8 IDTD motor was returning about 25 mpg when we bought her, 5 years later, 40k miles and with 70k on the clock it returns about 27-28 mpg. Mixed driving.

The engine has now run-in!!

Also I'm convinced that regular use helps all the moving items keep loose.
 
Bigpeetee said:
Our 2001 Kontiki with a 2.8 IDTD motor was returning about 25 mpg when we bought her, 5 years later, 40k miles and with 70k on the clock it returns about 27-28 mpg. Mixed driving.

The engine has now run-in!!

Also I'm convinced that regular use helps all the moving items keep loose.
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That extra one and a half Ton makes a difference. :cry:
 
It always used to be that peak efficiency and mpg coincided with the point in the rev range where the torque curve and the bhp curve intersected. Of course the mfr should also have used gearing to suit that point on the engine power curve also.

I also agree that a bigger engine often aids economy. Maybe not if you drive in Norfolk or Holland but if like me you are in steep hilly areas a lot, then a bigger torquier motor is very likely to be more efficient.

I just worked out mpg after getting back from a weekend in Powys, staying overnight in slightly snowy Llanidloes. All of the route was the scenic stuff I.e steep, windy, narrow stop start slow stuff with some tough climbs. Ole Sully averaged 26.1 mpg. Not bad, but more GP would have meant pulling a taller gear more often and better mileage.

If I get out of Wales onto flatter more flowing roads where Sully can lollop along in top without a lot of gas pedal and we pick up average speed and mpg straight away.

Footnote: Sully is quite low geared, needs to be with only 75 naturally aspirated dobbins to haul a lwb hi-top twin-wheel axle, 3.5tonne gross LDV Convoy.
 
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Rolls Royce tried to improve that transmission and managed to make it worse so gave up. That would be a good Buick to buy.
 
MPG does make a difference if you are a poor pensioner.

Comparing my old Romahome with the Sundance I have now - 46 MPG v 28.5 MPG - I spent a good £600 more on fuel over 12 months and similar mileage - that £50 a month would have been useful in the housekeeping budget rather than in the travel budget!

Insurance/tax/MOT/servicing added up to a bit less as well. Wish I'd never upsized!
 
Hymer b544

Hymer fiat Ducatoi base vehicle 2.5 td. 1995 model low mileage hit 30 regularly and even more depending on weather,
No exc,s or any of the fancy gear .good old fashioned engineering and setting up to maximise.but U.S. H,g ,v pros Ken how to do this����
 
I wish I could boast of my fantastic mpg..... but I can't. 20mpg average.... but I dont drive to be frugal, I drive to the conditions.
I try to stay at about 65mph on the motorways, and have to stay at 50mph max on the A roads. I have done 90mph though, and there was more left, but chickened out (or maybe it was nag nav informing me of the error of my ways).
 
27 mpg sounds good for that school bus. Mines half the size but I can get 40 mpg on a run without trying too hard. I use the cruise control most of the time on m/ways 60-65mph and A roads 50-55mph.
 
We have a self build van conversion on a 2.1 Mercedes Sprinter with 153 k on the clock a 2003 model , and have logged all the fuel and mileage over the last 6 months and it is our only form of transport so it is a mixed usage of local short town work and long runs and it worked out over just short of 5000 miles at bang on 32 MPG , well pleased with that love it and never was a steady driver 70/75 on the motorway and who me sir every where else
 
VW T5. 2.5 174 bhp. Can get 600 miles to a tank of fuel if eco driving. Highlands and Islands single track heaven normally 41 mpg. Bhp=mpg. :o
 
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