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Post by mauiboy on Jan 28, 2011 21:56:16 GMT -6
Interesting, dropped to 89 and my unscientific WOT up the hill test seemed to add a couple of mph into a stronger headwind than normal. I'll revisit in a few months when I have more mileage data. That is what I would have expected, but not what I have seen in the past.
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Post by mauiboy on Jan 27, 2011 23:56:39 GMT -6
That mostly matches my understanding but not always what I have witnessed. I do however agree with your comments. Some oddities I have witnessed, on normal compression (9.2:1 for the gas, 18:1 for the diesel) car engines I have routinely noticed better results with BP ultimate as compared to BP normal grade fuel and it is actually marketed as giving better mileage (an extra XX miles per tank etc, for the advertising standards agency to allow it there should be some truth to it?), the same going for diesel with a higher cetane rating. Part of the explanation given is the better detergents etc, but this is from a european perspective rather than an American one so it is possible there are different detergents used. There are also usually only 2 grades + diesel available rather than 3 grades of gas and no diesel which is more common in the US. I have no proven explanation for why I have witnessed 10-15% better fuel economy on a normal engine but I have. Perhaps euro fuels do spec detergents etc differently between lower and higher octanes as they rarely have a mid level? Second is that I believe it is common for 'plus' or 89/90 rated fuel to be a mix from the 87 & 92 fuels which may explain a little as to why there is more 87 ordered than sold directly. Also why do scoots have a sticker stating 90 octane + required? I'm not saying it is, just curious. Do the engines lower tolerances play a part? More likely to knock due to the delayed spark or poor design? No idea personally just interested. What do you all think? I know a lot of scoots are in the 8-9:1 range but I have seen a few 150's in the 10:1 range but that could be bad maths / bad translation / cut and paste drop selling etc. I'm thinking after a few more tank fuels I will switch down a grade and see after a few tanks of that what the results are? As I said, not trying to whizz on anyones chips, just curious as to what I am seeing  Thanks for starting the thread, there are a lot of misconceptions around octane ratings and at its most baisc the whole higher compression needing higher octane is true, but perhaps the situation is clouded by gas companies marketing of higher octane fuels being 'premium' and pricing accordingly? |
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Post by mauiboy on Jan 26, 2011 9:06:55 GMT -6
A scooter is a sign of good taste lol. Not sure I fall into any of Luke's categories so I guess it must be the youngsters one for me lol Or someone who is usually too tired to deal with a clutch and gears.
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Post by mauiboy on Jan 26, 2011 9:02:32 GMT -6
It's been as low as 70 recently, although we did manage some snow at 14000ft or whatever it is. It's hell for someone who is warm at 40 and is happy with a few feet of snow. We also managed 6 inches of rain in 90 minutes, the roads were fun that morning!
If anybody wants to trade a flat rate box of snow for one of stupidly hot air it can be arranged.
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