5.0 V8 Fueling and Efficiency Questions

LR4Slavo

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I only use Shell premium, almost 140k miles on the clock, average about 10 mpg. But I also run 35's on steelies and my wife's uses the truck to run errands and pick up/drop off the kids
Did you adjust the tire size in GAP or is the speedo keying off the OEM?
 

ktm525

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!70k on my 2011. Run regular here at sea level. Don't beat on it. Average about 15mpg. Truck is amazing. Didn't buy it for MPG's. Would note that my '07 XK convertible averages 25!!

low octane? I really believe that constant timing adjustment due to bad fuel is what is causing some of the tensioner issues we see. Can't see how running low octane at this compression ratio is a good idea.
 

ryanjl

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There are a few gas stations in town (BP) that have 93 Octane. They aren't nice, but they exist.

We have many more Quick Trips. They are the nicest gas stations in the country, in my opinion. But they only have 91 octane.

So, of course, my Rover takes precedent over my own personal wants and needs and I go to the crummier BP stations.
 

LR4Slavo

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low octane? I really believe that constant timing adjustment due to bad fuel is what is causing some of the tensioner issues we see. Can't see how running low octane at this compression ratio is a good idea.
Nah, just a bad design. I saw my old tensioner and guides, the steal pin on the tensioner almost wore right through the aluminum guide, perhaps more frequent oil change intervals would help but I don't think fuel quality has anything to do with it.
 

LR4Slavo

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There are a few gas stations in town (BP) that have 93 Octane. They aren't nice, but they exist.

We have many more Quick Trips. They are the nicest gas stations in the country, in my opinion. But they only have 91 octane.

So, of course, my Rover takes precedent over my own personal wants and needs and I go to the crummier BP stations.
Did you notice a difference on the higher octane go-juice?
 

ryanjl

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Not really. I think it was the video I posted earlier in this topic that scared me into finding the highest octane possible.
 

ktm525

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Nah, just a bad design. I saw my old tensioner and guides, the steal pin on the tensioner almost wore right through the aluminum guide, perhaps more frequent oil change intervals would help but I don't think fuel quality has anything to do with it.

You are likely right. I still think at sea level running regular is asking for trouble.
 

jlach993

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I religiously use 93 Octane. The $4-$5 cost savings at 20 cents per gallon @20 gallons is not worth it in my opinion. That saves enough for a candy bar lol. As to fuel economy I get around 10mpg when being an idiot on the streets. If I'm super conservative on nyc streets I average around 13 mpg. On the highway cruising on a level surface driving with* a head wind and very light throttle around 75mph i average around 18-21mpg...…but that's rare. I did get a stretch of 23mpg on the i95 making my way down to Florida a few years back for like 4 hours straight!!! That was the best haha.
 
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LR4Slavo

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I religiously use 93 Octane. The $4-$5 cost savings at 20 cents per gallon @20 gallons is not worth it in my opinion. That saves enough for a candy bar lol. As to fuel economy I get around 10mpg when being an idiot on the streets. If I'm super conservative on nyc streets I average around 13 mpg. On the highway cruising on a level surface driving with* a head wind and very light throttle around 75mph i average around 18-21mpg...…but that's rare. I did get a stretch of 23mpg on the i95 making my way down to Florida a few years back for like 4 hours straight!!! That was the best haha.
I've been keeping an eye on the live MPG lately and I wouldn't be surprised if I got between 20-23 driving straight through to empty on a relatively flat highway... but just like you, I've been enjoying the power of the 5.0L V8 a little too much, she moves pretty quick for a rig this size/weight.
 

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