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Discussion Starter #1
If I were able to get a nice motorway (freeway) where there was no limit and no other traffic.. if I could cruise.. at 155mph.. what would my MPG be at this speed? What is the range on a full tank of fuel at 155mph?
 

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efficiency would be somewhat low compared to lower-speed cruising. I would GUESS somewhere around 8-10mpg.

range = (mpg)*(18gal)
 

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Only one way to find out...


:M5launch:



dj
 

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Interesting question, has anybody worked out what the best speed for mpg in 6th is on the motorway?

Also you'd want to multiply by 15.3 imperial gallons here in the UK.
 

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When I was reading "The Driver" by Alex Roy, he states that the threshold between speed and fuel range/economy in his e39 m5 is at 127MPH, which resulted in about 18MPG... I would say his numbers are probably very accurate on this topic.
 

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So if I get pulled for maintaining an average of 127mph, I can blame the poor state of our economy and the obvious negative effects of our tax rate on petrol? Cool!
 

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Cool thread :)

I will check with 100% Cocoa (Barnie) as he is known for regularly doing his MAF tests in 6th gear on the German Autobahns ;)
 

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Next time i head up to Tucson, I'll push the button to reset the fuel consumption. Have a nice 3 miles section that I tend to take advantage of.
 

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Discussion Starter #11 (Edited)
Well this all stemmed from a silly discussion, a guy at work thinks that his diesel would complete a 500 mile trip faster than the M5 because it doesn't need to stop so often for fuel.. So I put a spreadsheet together and the results were quite interesting. Assuming the following:

155 mph top speed continuous
7 minute fill up time
8 miles per gallon (ish I am going from memory here)
70 litre tank
The cars average speed over 500 miles was 137.. comparing that to the golf..

139 mph top speed continous
5 minute fill up time
12 miles per gallon (I was surprised how fast diesel mpg drops off when they get to max speed)
50 litre tank
The cars average speed was 129mph...

The other interesting one.. was that if I took the limiter off and assumed 5 mpg and 180mph for the M5.. it actually didn't improve it's average very much as it emptied the tank so fast. I think in total the difference worked out as little as 6 minutes on a 500 mile trip but cost a lot more in petrol!
 

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Dont forget the cost of style. People will look at the M with envy and when they look at the Golf, they will laugh and say... ricer.

That alone should end that argument.

Not to mention how much more comfortable and safe the M is.

Lastly, how much faster does the M get up to speed vs. the VDub? That is some time to consder as well.

Silly VDub people... Farfegnugen my azz
 

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Mate if you saw the price of golf tdi's, and cost of fuel over here, you'd rethink that!
I'm selling mine and getting a passat tdi....
 

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OK, if you want to get technical about it...

The spreadsheet makes a good straight line example.

But begin to factor in how each of the vehicles perform at their top speed, and the difference will soon become greater as you factor in real world scenarios.

Add in traffic.

Add in passing power, somehow I think the ///M has a wee bit more [holding thumb and forefinger verrrry close together] passing omph than the VW and you are starting to add on more time to the VW's final arrival time.

Add in acceleration and time to arrive at top speed.

Then you have those intangibles, comfort, fear [how does that VW feel running at its top speed?] and you begin to separate even more.

And as previously mentioned, you'll look much better when you arrive anyway...
 
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When I was reading "The Driver" by Alex Roy, he states that the threshold between speed and fuel range/economy in his e39 m5 is at 127MPH, which resulted in about 18MPG... I would say his numbers are probably very accurate on this topic.
I have that very same book up in my room but have yet to get past the 1st chapter. Just been a busy time of my life with no extra time. If anyone knows this info well it would certainly be Alex Roy (like you said)...
 

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there is an article in the "M5 Gold Portfolio" book, which claims the "worst" MPG the car can get is 8. I assume this is at top acceleration, limited... I suppose if you have a chipped engine, you could do even worse.
 

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I have that very same book up in my room but have yet to get past the 1st chapter. Just been a busy time of my life with no extra time. If anyone knows this info well it would certainly be Alex Roy (like you said)...
It is a fantastic read! I highly recommended you pick it back up when you have the time.
 

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I reset my trip before both my track days, it will not go below 8.3 on mine, I have had 19mpg showing at a steady 130mph too, must have been a favourable wind?
 

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It is a fantastic read! I highly recommended you pick it back up when you have the time.
Thanks buddy for the insight. I will make sure to pick it back up & start from the beginning again. As soon as I can find the time to start reading it (all the way through this time) I'm sure that I will enjoy it... ! :3:
 
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