The manual in the Raptor states the truck makes 400 hp on 87 and 411 hp on 91. I assume either the knock sensor or some other sensor detects the fuel quality and adjusts timing or whatever else accordingly to make the difference in power.
I know on older vehicles, running higher octane than what it's tuned for doesn't provide any benefits, but with the newer ones that adjust differently depending on fuel quality, I figured if 91 is better, possibly 93 is even better (bettererest! LOL). My findings seem to show the opposite though. Seems the computer will adjust accordingly for 87 to 91, but beyond that, it's a wash, and actually decreases mileage.
RESULTS:
Tank 1: 87 Octane My Raptor came with a full tank of 87 when I picked it up. Drove it all the way down to within a few gallons and filled it up with 93. Hand calcs showed averaged ~12.2 mpg (1st tank of 87).
Tank 2: 93 Octane Second tank drove it all the way down again, and filled up with 93. Hand calcs showed averaged ~13.2 (1st tank of 93). Improvement attributed to breaking it in.
Tank 3: 93 Octane Third tank drove it all the way down again, and this time filled it up with 91. Hand calcs showed averaged ~13.5 (2nd tank of 93). Marginal difference attributed to finishing off break-in and slightly more highway travel this tank.
Tank 4: 91 Octane Only about 1/3rd of the way into this tank, and same typical driving pattern as tanks 1-3, but a few miles after filling up, (about the point the 93 was run through the system and drinking 91), I noticed a considerable jump in fuel economy. Digital readout has NEVER gone above 14.3 on any tank before (i reset it every tank). First day of 91 I was seeing 15.3 on the same exact commute pattern. I'm still showing an average of 14.7-14.9 now a few days into it when typically I would show 13.9-14.1 on both previous tanks of 93.
It'll be at least a week before I need to fill up again, but I'll run the hand calcs, and do a second tank of 91 just as follow-up. My digital readout has always been higher than the hand calcs, but I expect this tanks hand calcs to beat the last two of 93 by a decent amount, and with almost 1,400 on the clock doubt it's attributed to break in at this point, especially since it was almost like a switch was flipped seeing the bump in mpg with this fuel.
Anyway just a general obersvation. I usually put in the better gas since it's only another $10-$15 a tank, but seems the truck actually likes 91 better than 93. I'll probably try 2 tanks of 89 and 2 tanks of 87 afterwards just to get a good comparison going, then step back up again, for long term results.
DISCLAIMER: If you're going to post and rant about you don't care about mileage, blah blah blah, just save your fingers the exercise and ****. It's nice that you don't care about your fuel economy, and your arguement that if you care about mpg you should buy a prius is as stupid as it gets, save your breath, or I should say save your keystrokes. I'm simply posting up some results I thought were interesting. And what the heck, if the truck drives and responds exactly the same on two different fuels but gets better mpg on one than the other no other variables changed, that's more money in my pockets to spend on mods!
I know on older vehicles, running higher octane than what it's tuned for doesn't provide any benefits, but with the newer ones that adjust differently depending on fuel quality, I figured if 91 is better, possibly 93 is even better (bettererest! LOL). My findings seem to show the opposite though. Seems the computer will adjust accordingly for 87 to 91, but beyond that, it's a wash, and actually decreases mileage.
RESULTS:
Tank 1: 87 Octane My Raptor came with a full tank of 87 when I picked it up. Drove it all the way down to within a few gallons and filled it up with 93. Hand calcs showed averaged ~12.2 mpg (1st tank of 87).
Tank 2: 93 Octane Second tank drove it all the way down again, and filled up with 93. Hand calcs showed averaged ~13.2 (1st tank of 93). Improvement attributed to breaking it in.
Tank 3: 93 Octane Third tank drove it all the way down again, and this time filled it up with 91. Hand calcs showed averaged ~13.5 (2nd tank of 93). Marginal difference attributed to finishing off break-in and slightly more highway travel this tank.
Tank 4: 91 Octane Only about 1/3rd of the way into this tank, and same typical driving pattern as tanks 1-3, but a few miles after filling up, (about the point the 93 was run through the system and drinking 91), I noticed a considerable jump in fuel economy. Digital readout has NEVER gone above 14.3 on any tank before (i reset it every tank). First day of 91 I was seeing 15.3 on the same exact commute pattern. I'm still showing an average of 14.7-14.9 now a few days into it when typically I would show 13.9-14.1 on both previous tanks of 93.
It'll be at least a week before I need to fill up again, but I'll run the hand calcs, and do a second tank of 91 just as follow-up. My digital readout has always been higher than the hand calcs, but I expect this tanks hand calcs to beat the last two of 93 by a decent amount, and with almost 1,400 on the clock doubt it's attributed to break in at this point, especially since it was almost like a switch was flipped seeing the bump in mpg with this fuel.
Anyway just a general obersvation. I usually put in the better gas since it's only another $10-$15 a tank, but seems the truck actually likes 91 better than 93. I'll probably try 2 tanks of 89 and 2 tanks of 87 afterwards just to get a good comparison going, then step back up again, for long term results.
DISCLAIMER: If you're going to post and rant about you don't care about mileage, blah blah blah, just save your fingers the exercise and ****. It's nice that you don't care about your fuel economy, and your arguement that if you care about mpg you should buy a prius is as stupid as it gets, save your breath, or I should say save your keystrokes. I'm simply posting up some results I thought were interesting. And what the heck, if the truck drives and responds exactly the same on two different fuels but gets better mpg on one than the other no other variables changed, that's more money in my pockets to spend on mods!
