87 octane economy tune for LNF?

[skip_jones]

You and me both. It was 3.87 for 93 yesterday. Which is why I am not in a hurry to get the car done lol.

two of my other cars are v8's. oh the pain, the pain.

[Jaxon]

I drove to wichita kansas from st louis in my hhr, doing ~75, my pos only got like 25mpg... need more cruise timing and shit I guess... damn brick lol

[rnjmur]

I have found that the MPG on the LNF really starts to drop off once you go over 70 mph. I am not sure what it is, but there is some magical point around 70 where the car just starts to get much lower fuel economy.

The stock cruise timing tables are pretty well maxed out already, most see some KR and remove a bit, best advice is from cmiller above.

I average 27.x on the 50/50 E blend.

I had some knock on the stock tables, but once I smoothed the whole table and redid it by hand I was able to pick up quite a few degrees of timing in the low to mid range.

[gmtech16450yz]

I have found that the MPG on the LNF really starts to drop off once you go over 70 mph. I am not sure what it is, but there is some magical point around 70 where the car just starts to get much lower fuel economy.
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I've noticed that too, was going to try to figure out why and if anything in the tune can be tweaked to help it but never got around to it. I'm gonna say on my Redline there's a 5mpg difference between 65 and 75mph.

[nester]

I have found that the MPG on the LNF really starts to drop off once you go over 70 mph. I am not sure what it is, but there is some magical point around 70 where the car just starts to get much lower fuel economy.

I've kinda noticed the opposite.. Mine seems to be better around 80 than it is at 70. Don't really have any numbers to back that up, but I was avging 29-31 when I was commuting from Houston to Dallas. I beat on it like it was a bad dog in the city, but I was driving ~1000 miles a week on the interstate.. to the point where my AVG speed on the infometer was between 55-60mph. Which is hard, it's like 37 now.

[rnjmur]

I've kinda noticed the opposite.. Mine seems to be better around 80 than it is at 70. Don't really have any numbers to back that up, but I was avging 29-31 when I was commuting from Houston to Dallas. I beat on it like it was a bad dog in the city, but I was driving ~1000 miles a week on the interstate.. to the point where my AVG speed on the infometer was between 55-60mph. Which is hard, it's like 37 now.

I haven't really been able to do any sustained speeds above 75mph (traffic is too bad here to go any faster than what everyone else is driving), but I know that if I drive 60 I can average about 32-33 mpg, at 70 I can average about 30-31 and at 75 I average about 25-26.

On my LSJ it was the opposite. I would average about 26-28 mpg at 60, 30-32 mpg at 70 and 32-34 mpg at 75. I thing that on the LSJ what pulley you are running makes a big difference as to how your mpg is at different speeds.

[T-Man]

I haven't really been able to do any sustained speeds above 75mph (traffic is too bad here to go any faster than what everyone else is driving), but I know that if I drive 60 I can average about 32-33 mpg, at 70 I can average about 30-31 and at 75 I average about 25-26.

This is exactly how my car is but 65 instead of 60 shows 32-33.

Crazyness