MPG?

moodrater

Our van just returned 33.2mpg over 550km including about 120km of motorway, 240km of r roads, 60k of urban and the rest n roads.

Anyone looking at dipetane and not already put off by their outlandish claims should note that the single vehicle they like to quote actual factual emmissions data for is a 1989 american 7.3l diesel heap of ****e so unless your driving something like that don't expect the mpg improvements quoted. Practically every figure they give is preceded by non scientific terms like 'up to' or 'about' which is jarring if you're from a scientific or engineering background.

Its good for getting bangers through the nct but your moneys probably better spent on repairing the cause of emissions failure unless your doing very small miles. A much more realistic expectation is the 3% quoted by topaz for their fuel which includes ultra super dooper miracle additives for free. People with efficient diesels may see no statistically significant difference at all.

Irishgoatman

My vehicle has a 1986 ,1ltr petrol engine, 2 berth.

As I said earlier, it has no emission problems, but despite the fact that it's built with the wind resistance of a brick I feel I should do better than 30mpg. I rarely go over 50mph because that's the speed it likes. Because the gear box is very low ratio I do often find myself doing 30mph and still in 5th gear, which I'm sure doesn't help the fuel consumption.

I don't know the price of Dipitane but if it's not too dear, anything that gives a little help will be welcome.

I take all claims of greatness with a large pinch of salt, to the extent that I quite often don't believe myself!.

Check your leaf springs. If they are straight or can potentially bend against the bow then you stand to gain a lot in fuel economy by adding a helper leaf and maybe even new shocks.
Self-builds tend to be closer to laden weight than not.

Aidan_M_M

Sir Liamalot wrote: »

Check your leaf springs. If they are straight or can potentially bend against the bow then you stand to gain a lot in fuel economy by adding a helper leaf and maybe even new shocks.
.

How so , Liam?

Grand Aidan...as per usual I'm making some assumptions here.
afaik a LGV is designed to compromise road holding against cargo capacity on a sliding scale of about 2 tons.
Vans are not designed to be fully laden.
They move quickly and efficently when empty and hunker down when transporting.

If you know you will always have an extra 0.5ton to 1.5ton in the back you can afford to firm up the suspension and reduce fuel consumption in vibration, differential offset, vertical forces on the universal joint of the drive shaft etc.

I've added 3mpg swapping my leaf set with a lutton body.

http://www.portlaoisesprings.ie/

Aidan_M_M

Sir Liamalot wrote: »

Grand Aidan..
If you know you will always have an extra 0.5ton to 1.5ton in the back you can afford to firm up the suspension and reduce fuel consumption in vibration, differential offset, vertical forces on the universal joint of the drive shaft etc.

.

Fair play , I'm sorry if you were thinking I was being smart. That's a well detailed and informative answer! Fair play. Makes sense too, apart from the vibration bit , I don't really get that , unless the propshaft is very short.

cipro 55

Anyone know how accurate the MPG read out is on the dash of the transit.

Aidan_M_M

Aidan_M_M wrote: »

Fair play , I'm sorry if you were thinking I was being smart. That's a well detailed and informative answer! Fair play.

No worries, not at all, I am a bittov a chancer you correct me when I'm wrong all the time. Keep it up it's educational

vibration comes into play when the axle is moving. The more rigid the back axle the less fuel is wasted by the differential sending more power to one wheel.

It's a saving probably more suited to RWD self-builds.

moodrater

cipro 55 wrote: »

Anyone know how accurate the MPG read out is on the dash of the transit.

The average on the newer one is supposed to be fairly accurate over a couple of tanks but the only scientific way to measure mpg is by brimming the tank (and waiting and filling several times to ensure that air and foam has escaped) and recording the odometer.

Irishgoatman

moodrater wrote: »

The average on the newer one is supposed to be fairly accurate over a couple of tanks but the only scientific way to measure mpg is by brimming the tank (and waiting and filling several times to ensure that air and foam has escaped) and recording the odometer.

Quite right but don't forget to record the anount of fuel that goes in each time.

I've been doing this since the late 70's when I had a Vauxhall Victor car. By doing that, filling the tank each time, recording the odometer reading, subtracting that reading from the previous reading and dividing that by the amount of fuel you put in. With the Victor, whenever the comsumption went up it told me that the air filter needed changing!. The note book that I've got for the car actually goes back over 4 cars!.

It helps by letting you know that something needs checking even though you might not notice it whilst driving.

You can take the volume readout off the receipt when you buy fuel. Always having a full tank will increase your weight thus reducing MPG. You can save here too if you fill according to range.
Jaysus we're all such nerds...:o

Irishgoatman

Sir Liamalot wrote: »

You can take the volume readout off the receipt when you buy fuel. Always having a full tank will reduce MPG by 2 (for me anyways).
Jaysus we're all such nerds...:o

That's fine if you bother/remember to get a receipt.

But at least we are thinking nerds, unlike trainspotters:D.

I fill by volume not by (cheapest) price. Makes more sense to me.

Irishgoatman

Sir Liamalot wrote: »

I fill by volume not by (cheapest) price. Makes more sense to me.

Price doesn't come into it when keeping a check on consumption.
Just distant travelled (miles or km) from one full tank to the next full tank as long as you've kept a note of any fuel put in between the full tanks.

Comes into it when you pay for it though...
Wasn't that the point in the first place?

*Kol*

Sir Liamalot wrote: »

Comes into it when you pay for it though...
Wasn't that the point in the first place?

It only depends on what value you put on the use of your MH/camper. For me I get more enjoyment out of the use of the MH than the cost of the fuel.

Grand I'm not sure how relevant that is to a MPG thread though. Surely the only reason to monitor it is to increase your range to further enjoy your MH? Or as Irishgoatman does to monitor mechanical health.

*Kol*

I should have elaborated above. I dont worry about the fuel consumption so much, if i want to use the MH i need to put fuel in it regardless of the fuel consumption. The MPG of the MH is part of the running cost but by no means outweighs the enjoyment i get from the MH, I thought that might be relevant in the MPG thread and something to consider for people who may be unnecessarily worrying about it.

I do keep an eye on it out of interest and for health monitoring purposes though. It's a good idea as you do to fill according to the length of journey you intend to do. Also not filling up with water, heavy unnecessary items (wife and family!!!) etc helps keep the weight down and aids keeping the fuel consumption down.

Of course one of the heaviest things on fuel consumption can be your right foot!! It's always tempting to eat up the miles/kms on the motorway at 120 kmh but you really notice the increase in consumption.

Irishgoatman

I think that when Macspower started this thread it was just to see how different vehicles did on fuel consumption.

This sort of information is always nice to have. You can either give yourself a pat on the back for buying the right vehicle or give yourself a lot of sleepless nights wondering where all the fuel is going:D.

niloc1951

I tend to travel at 90Kph +/-5Kph. This gives me in the region of 26MPG, but it can go as low as 21MPG if I travel at 110Kph or more. Being as aerodynamic a brick pushing above 100Kph or a strong headwind can really decimate the MPG.
BUT, it's really all part of the 'lifestyle' cost and if the relatively low MPG of a motorhome bothers a person unduly then perhaps a tent and car might be a better option

BTW, one should always park up with a full tank. The 'bugs' mentioned HERE will be supplied their water to grow from the condensation which forms on the insides of the walls of empty or part empty tanks as they are left standing for weeks on end. I have been told by a main dealer foreman mechanic that the current diesel which now contains a percentage of Bio Diesel suffers more than the old stuff with this problem.

Irishgoatman

With Niloc mentioning parking the camper up (for the winter in my case), don't do what I did 2 years ago.

When I took the camper out for an overnighter at the end of winter, had a nice night out, filled up with petrol near home, took the record book in the house and did the consumption calculations as usual then spent the next couple of days trying to figure out why I had only got 24mpg rather than the usual 30!!.

Took me 2 day before I remembered that through the winter I was starting her, and leaving the engine running, for around ten minutes every 4 or 5 days for nearly 3 months without any mileage going on the odometer:o. Just moving her backwards and forwards a couple of feet for the sake of the tyres.

Pillock or what.

Same thing happens if you charge the leisure batteries off the alternator while standing. Genuine miles..ha!

niloc1951

Irishgoatman wrote: »

..................... filled up with petrol................

Perhaps you meant diesel!, but don't worry if you have a petrol engine as the effect I was talking about in my earlier post only happens to diesel fuel.

BTW it is better to go for a short drive to fully warm up the engine by giving it a bit of work to do, give the tyres a proper run and warm up the various transmission oils and greases.
Such a run shouldn't consume more than a litre of fuel and it would be money well spent.

Irishgoatman

niloc1951 wrote: »

Perhaps you meant diesel!, but don't worry if you have a petrol engine as the effect I was talking about in my earlier post only happens to diesel fuel.

BTW it is better to go for a short drive to fully warm up the engine by giving it a bit of work to do, give the tyres a proper run and warm up the various transmission oils and greases.
Such a run shouldn't consume more than a litre of fuel and it would be money well spent.

It had better be petrol as that's all I've ever put in it:). It wasn't bugs or anything that I was worried about it was just the parking up that reminded me of the missing petrol:D.
Not always easy to get the camper out from behind the tractors and starting any vehicle on a regular basis does just as well I've always found, as long as it gets a bit of movement for the sake of the tyres and to move the gears around.