Fuel economy unofficial

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Diesels 2WD


1.9TD AAZ fully loaded westfalia hightop whilst on holiday with a family of 4 average MPG 28.2 over 500 miles and 2 fills. The gear box and tyres are stock on this van so it is under geared. I ran it between 3-3.5K revs or 55-60mph on the motorways but there was some local driving in there too not more than 20% though. All filters and oils all changed within the last 1000 miles before these readings.

Diesel Syncros

SyncroAnd101: Expedition Camper (Syncros) over approx. 5,000 miles from GBto Southern Morocco and back, off-road, sand, snow, rocky roads part way, part high altitide (Atlas Mountains)

1.9 mTdi, off-road tyres, high-top, fully loaded, roof rack etc. + 2 people == 30.93 mpg.

-- Just as a comparison, I have done Cornwall and back and North Wales and back in the last month - fairly well loaded, not to the hilt, all with Mud Terrains and roofrack+kayak etc, Did the fill, then refill at destination noting mileage, things have got better with the longer 3rd and 4th. Was about 34 mpg, driving about 65mph most times.

With chargecooler and oil cooler. Boost is about 0.5 (JX turbo). Temp hardly budges most times, unless on a long steep climb.

MudLark: Just got back from Croatia last Sunday; 4220 trouble free Kms compared to last years excitement. Official MPG was 28.03 mpg which is about 3mpg better than I have ever got before and I'm wondering why. Last year 25 mpg on similar destination, though different journey

Syncro 16 Westy Expedition Camper, fully loaded, ECU injection, intercooled, Tdi, high gears, winch etc

MPG DieselTdi Mudlark 2010.jpg

Peasant: 1.6TD Average of 8.5l/100 km on short-ish country road runs (33mpg) Around 8 l/100km on longer runs (35 mpg)

SyncroG: 1.9TD Down to around 30mpg nailing it up and down the hills here, on a motorway run it's better, sometimes high 30's. Gets a lot more wind and engine noise once you go over 55 so I'd imagine it'll drink badly soon after 60mph.


MPG DieselTdi Slobbo 01.jpg

With odo readings adjusted +10% for larger wheels and tyres, TD diesel MPG DieselTdi Slobbo 02.jpg


Syncro Tristar Diesel 1Z Tdi With odo readings adjusted +11% for larger wheels and tyres. Tyre type ? MPG DieselTdi Keeno 01.jpg

HarryMann: 1.9TD Syncro Doka 15" Machos (knobbly mud tyres); overfuelled a bit and boosting to about 14 psi - Accurate speedo, odo error about -2%..

Lots of off-road, also lots of problems, manifolds coming loose, blocked filter changed at 2650 miles, turbo probs etc., some towing towards 5,000 mile mark.. also, most long-dist cruising usually nearer 70 than 60, sometimes 75. Have towed heavy trailers, have carried 3,000 lbs + in back, crawled for miles through lanes as well as sat on French motorways in high heat.

NB. Actual points plotted are where a full fill back to brimming is made, intermediate fills included in next brim, so no guesswork really, other than exact brim-point slight variance, which soon becomes insignificant after a few thousand miles. Note that the curve to use to judge mpg 'trends' is a rolling mean of last 3 or 4 fill-to-fill figures (yellow curve). Pink is actual MPG to date, so right hand end of line is what it's done since recordings started. Blue is brim-to brim, so gives you a good idea how misleading even a whole tank brim-to-brim can be.

So I have driven about 6,000 miles since starting this record and she has done EXACTLY 22.98 (uncorrected) and 23.44 mpg (corrected by 2%) Good or bad, there is no argument using this method. She can do 27 and also worse than 20 when going is tough, loaded or needs an airfilter change. I can also see clearly the results of tuning, adjustments, improvements and heavy footed driving! I should also know quickly when she is not running right. Also if someone is siphoning my fuel :)

Consumption G208THV 03.jpg

Petrol 2WD

Petrol Syncro

Mudlark: 2.1 Autosleeper down to Corsica and back, 2+ 2 on board plys kit.

trip in 2003 without prop trip in 2004 with new VC and prop

Both similar trips over similar routes brimmed to brimmed and recorded fill by fill producing:

2003: 2990 Miles 144.51 gallons £500.83 20.69mpg

2004: 2744 Miles 131.7 gallons £460.10 20.83mpg

Syncrosimon:2.1 16" Camper to Corsica and back, 2+2 and loads of kit.

trip in 2008 with de-coupler and new VW DJ engine running 3/4 on 98 octane 1/4 95.

4102km, used 484 litres of un-leaded. To my calculation that is 24mpg.

This was mainly flat out or near flat out running at 120kmh then on the peages.

akira28: 2.1 DJ Syncro

19 town & country roads 22 on the motorway normally around a steady 60MPH.

Average over the last 7 years is 20.38mpg

Toomanytoys: 1.9 DG Syncro, 20 ish local stuff.. 24 on a run at 60-70

..lee... My 2.1 does max 23mpg motorway @ 70 ish. empty.

Fully loaded me, mandy, 2 kids and the dog got 19mpg over i think about 700 miles.


IanHulley: 2WD - 2.1 - DG carb - on LPG I get 18.2mpg.

Others I've spoken to with a similar setup @ 60-65mph, whether 4 or 5 speed boxes, get the same mpg.

MPG Spreadsheets (Download)

XL2003 MPG Spreadsheet(Miles Odo)

XL2003 MPG Spreadsheet(Kilometers Odo)

Click link and then 'Save As' to your local disk drive before opening to use.

In Internet Explorer, if the spreadsheet just opens, then use the workbook File.. Save As menu item.

i.e. don't use the spreadsheet on-line

First select the cells with dummy data, then Clear Contents, ready for your first row (initial brim) which of course won't produce any figures until your next fillup. If you don't brim, just add that figure(litres) to the next time when you do brim

NB. Don't forget to hit the File... Save button everytime you enter a new row of fuelling data

The spreadsheet contains a data sheet and a chart. The datasheet is protected to prevent inadvertent entry of data into formula cells. Yellow cells are for data entry, one row at a time.

A mileometer factor can be entered into the datasheet to adjust for tyres (pink cell to right, no cheating! :)

The chart should be left alone unless you are XL power/developer user level, though the chart title should be changed There is a Macro in Tools... Macros for saving the chart as .jpg image to C:\temp (will overwrite any existing so rename if reqd. immediately). Alternately you can double-click the chart (on a blank area) to Save it as a jpeg image to your c:\temp directory

PM HarryMann for more detailed instructions (I will write a usage/FAQ page and include it in the workbook, some time soon)

Slobbos MPG calculator

I created the spreadsheet to allow me to compare vehicles so that I could make an educated choice. It will also work out the pay back time for LPG conversions.

To use it you input;

The current fuel prices per litre (Petrol, Diesel and LPG)

The capacity of the fuel tank (Petrol, Diesel and LPG) automatically works out the effective capacity of the LPG tank

The MPG of the vehicle(s) - Diesel, Petrol - automatically works out the LPG MPG based on the petrol value.

The trip/mileage. This is over a period of time (like a year or the for the time you intend to keep the vehicle) or for a particular trip (maybe an expedition to Morocco)

For business use calculations you can change the mileage allowance values and the business use mileage.

For LPG calculations - Annual Mileage

For LPG calculations - Cost of the conversion

It will work out for you;

How far you can get out of a full tank of fuel

The cost of a tank of fuel

The litres used and cost of that fuel over the set mileage - for both total and business use

For business use it will work out how much your tax allowance will give you back and how much you have left after you pay for the fuel.

The payback time if you want to do an LPG conversion yourself.

To download go to [1] http://www.aircooledcrazy.com and click on the link for Fuel Calculator.

If you find it useful let me know. Also let me know if it could be improved.

T25 Power requirements (drag)

Drag Vs Speed (2WD bus).jpg

Power Vs Speed (2WD bus).jpg

Power Vs Speed (Development graph)).jpg