JimAttrill Posted November 13, 2008 Share Posted November 13, 2008 Here are the figures: Total since 1996: Kms: 237 924 litres: 24 465.53 Which is 10.32 l/100 Since installing water injection: (not always used for various reasons) Kms: 6 113 litres: 611.72 Which is 10.01 l/100 A gain of 3% Quote Link to comment Share on other sites More sharing options...
Guest otchie1 Posted November 20, 2008 Share Posted November 20, 2008 Here are the figures:Total since 1996: Kms: 237 924 litres: 24 465.53 Which is 10.32 l/100 Since installing water injection: (not always used for various reasons) Kms: 6 113 litres: 611.72 Which is 10.01 l/100 A gain of 3% 3% sounds a lot like normal variation to me Jim, I can vary by more than that with tyre pressure. Any sign of water in your sump oil? Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 20, 2008 Share Posted November 20, 2008 Yeah FFS Jim you should get one of those airflow things that go in the intake and make the air all swirly - they increase your mpg by at least 25% Couple it with a K&N and your engine will never be the same again Fuel magnets are good for 30% I've heard, and some of that magic oil additive stuff adds 40% so pump your tyres up to 90psi to add another 5% and your 110 will be completely free to run [/windup] Quote Link to comment Share on other sites More sharing options...
orangemach5 Posted November 20, 2008 Share Posted November 20, 2008 I run water injection on my 3.0 perkins turbo in my rangerover, i use a 50/50 mix of water and methanol though. The reason for fitting mine though was to increase performance and not economy, hence the aditional methanol. It makes a fair bit of difference to performance and increases boost on the top end by 2psi. Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted November 21, 2008 Share Posted November 21, 2008 Jim - do you find that your normal fuel consumption is better in summer than winter? That's certainly what we see with vehicles in work. 3% is on the edge of measurable - if it was less it could be criticised as 'within margin of error', but more than 3% I'd start to be suspicious about whether you've backed off the throttle to make yourself believe its working... Quote Link to comment Share on other sites More sharing options...
JimAttrill Posted November 21, 2008 Author Share Posted November 21, 2008 All these figures come from an Excel spread sheet that I programmed to work out fuel consumption back in 1996 when I bought the 110. The only variation from about 10.28 to 10.32 I have ever seen is when driving extensively in the Kruger park where I rarely go above 40 kph. And of course that 10.32 figure includes those holidays. There is no seasonal variation as far as I can see, possibly because it never gets really cold here, though it does get very hot sometimes. I should use more fuel in the summer because of the aircon, but in fact I hardly ever use it preferring to open the vents and the sunroof. Anyway, if anyone wants to look at the spreadsheet figures, pm me with your email address and I will send it. Of course, all these consumption figures are not really accurate because my odometer overreads by exactly 5%. On the other hand it always has, and I have not changed my speedo. So my 10 l/100 kms is actually more like 10.5, something like 27mpg or so. Tyre pressures? I have always used 2.5 bar and check them often using my own compressor and gauge. Tyre size? I started off on General SAG 750x16 radials but switched to BGG AT 235/85x16. I have always used 15W40 mineral oils in the engine. I recently changed the main gearbox oil from MTF94 to Redline MTL, but they are of the same viscosity. Oil in the water? No. Remember that the high-tech water pump (Disco headlight washer pump) only runs above .3 bar boost or 5psi if you like. Quote Link to comment Share on other sites More sharing options...
smo Posted November 23, 2008 Share Posted November 23, 2008 Opening sunroof and windows uses more fuel than running air con....... Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted November 24, 2008 Share Posted November 24, 2008 That rather depends how fast you're going... Quote Link to comment Share on other sites More sharing options...
Guest otchie1 Posted November 24, 2008 Share Posted November 24, 2008 That rather depends how fast you're going... True but the difference in rolling radius of tyres between new and 8mm worn is about 3% - it's just so small a % for the results to only be described as marginal. The only way to settle this would be on a dyno but that is beyond the scope of Jim's experiment. BTW Jim, how long before your savings pay back your investment in equipment (and time)? Quote Link to comment Share on other sites More sharing options...
David Sparkes Posted November 24, 2008 Share Posted November 24, 2008 I think some of you miss the point about Jim's results. Because he has a long baseline to begin with, any variations in season, daily travel pattern, or mechanical condition tend to be lost in the overall figure. They become little ripples in the line, not peaks and troughs. Now he is creating a long post injection baseline, where again minor variations in day to day usage, temperature, tyre pressures, etc, get lost in the sheer mass of data. Thus if the figures show a 3% gain, that's what he is getting. Concerns about daily temperature, tyre pressures or patterns, windows open or closed, etc, only become important if you are comparing last weeks figures with this weeks figures. A dyno test would be useless for this experiment, as it is not about maximum power at any particular rpm. Jim's first results over 6000km show a gain, that means it's sensible to carry on collecting data. The greater the time / distance the post injection data extends for, then the more solid the comparison becomes. Keep up the good work Jim. Quote Link to comment Share on other sites More sharing options...
sotal Posted November 24, 2008 Share Posted November 24, 2008 Tyre size? I started off on General SAG 750x16 radials but switched to BGG AT 235/85x16. I thought I'd posted this already but when did you change the tyres? Quote Link to comment Share on other sites More sharing options...
Guest otchie1 Posted November 24, 2008 Share Posted November 24, 2008 I think some of you miss the point about Jim's results.Because he has a long baseline to begin with, any variations in season, daily travel pattern, or mechanical condition tend to be lost in the overall figure. They become little ripples in the line, not peaks and troughs. Now he is creating a long post injection baseline, where again minor variations in day to day usage, temperature, tyre pressures, etc, get lost in the sheer mass of data. Thus if the figures show a 3% gain, that's what he is getting. Concerns about daily temperature, tyre pressures or patterns, windows open or closed, etc, only become important if you are comparing last weeks figures with this weeks figures. A dyno test would be useless for this experiment, as it is not about maximum power at any particular rpm. Jim's first results over 6000km show a gain, that means it's sensible to carry on collecting data. The greater the time / distance the post injection data extends for, then the more solid the comparison becomes. Keep up the good work Jim. No, I think you've missed the point. For the complete history of the data Jim was driving pretty much as Jim (however that is). Now, since he is so concerned about fuel economy that he has fitted a water injection system to his engine, he is driving as Jim-wot-is-desparately-tryin-to-save-fuel. A different beast. As the data only shows a 3% improvement and as 3% is on the border of statistically significant effect then the result is 'not proved'. The tyres, air pressures, weather stuff are all just examples of much easier ways to save 3% of your fuel bill. A dyno test would be very useful as, surprisingly, a more efficient engine produces more power from a given amount of fuel. Quote Link to comment Share on other sites More sharing options...
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