I fitted winter tyres a couple of weeks ago, and I had noticed that along with the noise, my fuel economy had gone down. I filled up yesterday with Shell V Power 100 just to see if it was any better or worse. Now admittedly most of the miles I did were on the motorway, but I have done many runs before like this one (Solothurn-Strasbourg-Solothurn), and I got more miles out of my tank than I did in summer. 508 km from 28 litres. Had I had summer tyres on, I am sure that I would have got a good deal more. More expensive, but much more mpgs.
- Thread starter gpovanman
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malcolm
& Clementine the Cat
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That's 50mpg. Pretty good even for a 4. Normally I get around 45 to the gallon on a run driving at 70mph, and a bit more going more slowly.
My winter tyres are taller than the summer tyres, so they lower the gearing and improve economy on s run. The winter tyres aren't too bad for rolling resistance these days.
My winter tyres are taller than the summer tyres, so they lower the gearing and improve economy on s run. The winter tyres aren't too bad for rolling resistance these days.
angel
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That's 5,5 lt/100km...pretty nice! What type of engine do you have? I have gone down to about 5,8lt/100 km on my 845cc with Zenith 28IF carb on motorway. Side note on "V-Power" and other so-called "special" types of petrol. There is a lot of advertising tricks on them that are not correct from an engineering or chemical point of view.Octane number does not describe the thermal energy that a fuel can give,only its resistance to pinking. So a good old 845cc R4 engine will not know the difference between 91,95 or 100 octane petrol since it was designed to run on 86 octane petrol. Only if you raise its compression ratio and/or alter its ignition curve will a higher octane fuel be necessary (but this would be a necessity to protect the engine,not a way to gain some power).
I have a 1990 Clan model with the 1108 cc engine. It had 57,000 kms on the clock when I bought it in April, and since then I have done just over 20,000 in it, and I ALWAYS log my fuel stops, so when I can be bothered, I will be able to give you a long term figure. I also found that when running on V Power, the engine did not need choke for quite as long. Just to rub it in a bit, in Switzerland, V power is 70p per litre, and ordinary 95 octane is about 63 p per litre!!
I have eventually done my sums, and have worked out that over the first 17180 kms, it did an average of 6.113l/100kms, or about 44ish to the gallon. I now only use premuim petrol, instead of budget stuff, so it may well improve even more. Does anybody know if it will have the same effect on a low compression V8, because I am away from it at the moment, but have to pick it up at Christmas, and that is a 650 mile run.
bantamallan
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petrol
my handbook says 98 octane for my GTL and on ordinary unleaded it pinks when pulling hard. I have just started using tesco 99 octane 83.9 here and fount it much better
my handbook says 98 octane for my GTL and on ordinary unleaded it pinks when pulling hard. I have just started using tesco 99 octane 83.9 here and fount it much better
malcolm
& Clementine the Cat
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That's a good point - the GTLs were set up to run very lean to start with, and wear in the distributors make them less tollerant to poorer quality fuels. I retard my ignition a bit to cope with unleaded.
The super fuels work well in modern cars where the electronics alter the timing on the fly. I guess similar results could be had in a GTL simply by not retarding the timing. Not economical in the UK with the cost of super unleaded, but I do treat the old girl to the fancy stuff in France where there is less difference in price.
Anyone tried bio-ethanol? I understand that so long as the flexible fuel pipes have been replaced in the last 10 years, and the choke is left out a little the R4 should run quite well on the stuff (for a proper job different jets might be needed in the carb).
The super fuels work well in modern cars where the electronics alter the timing on the fly. I guess similar results could be had in a GTL simply by not retarding the timing. Not economical in the UK with the cost of super unleaded, but I do treat the old girl to the fancy stuff in France where there is less difference in price.
Anyone tried bio-ethanol? I understand that so long as the flexible fuel pipes have been replaced in the last 10 years, and the choke is left out a little the R4 should run quite well on the stuff (for a proper job different jets might be needed in the carb).