Sounds like my '2009 F150 4WD 5.4 without "EcoBoost" is getting much better mpg's - about 20 on the highway - with regular gas.

 

Was that you I saw doing 40mph in the slow lane on the interstate the other day? While everybody else was going 65-70mph.

 

Tuners are already out here for these trucks. I had a tune using the sct xcal3 when I bought my truck a couple of months ago. Not only do the trucks go off of the knock sensors to sense octane, they also have widebands. It knows what is in the tank from regular gasoline to e85. I have logs of all of this if you want to review them.

 

Six to one half dozen to another. Knock sensors sense detonation NOT octane. Widebands sense A/F ratio's. I'm well aware of how the computers adjust to fuel, altitude..etc. We all know there is also a MAF that comes in play. The incremental changes that the computer makes for all the above isn't going to gain anyone 15HP and 15ft TQ just from fuel. If so, dyno it and show me that.

My main point was under normal driving conditions(trying to gain MPG) as I've stated 20 times already changing from 87 to 91+ is going to gain nothing if the engine isn't pulling any timing from 87. Period, if it does...then that 15hp/tq should easily show up on a dyno pull. IMO, not going to happen.

I'm also well aware of the SCT xcal3 and I rather wait for a few tunes to become available for a baseline. I've been in contact with Livernois Motorsports and they just started messing with the f150. I rather have them work out a good tune instead of myself creating a tune from scratch making 20 dyno pulls in the process since I'm not looking to build a race car out of the f150. If you have logs shoot them over along with your tune.

 

Any update on the mileage?

 

These trucks will get good mileage as soon as the fun wears off!!!! There again with this motor it may never wear off!

 

Why not just run a couple of tank fulls and see what happens? We have one guy who is doing just that and I'm interested to see what happens. Proof's in the pudding. My money says there will be an improvement, but might not be enough to justify the added cost. I'm certainly going to try it when I get my truck.

 

Well, I'm back at 24 miles to empty. After running a full tank of Premium 93 Valero Gas, my mpg went from 14.9mpg on regular 87 to 15.6mpg with the 93. Being 90% city driving, there are many variables that could fluctuate mileage (traffic conditions, ect). Because of that, I can't conclude for certain how much, if any, premium unleaded increased efficiency. As far as performance, the only noticeable thing I can state is that the engine seems to run a bit smoother on premium (most noticeable at idle).

I've decided to add another aspect of the experiment and fill up with a different brand. Per Blue07STX's suggestion, I will fill up with Chevron 87 octane. If I get better mileage with Top Tier 87 over Valero 93, then I will conclude that octane rating plays less of a role in fuel efficiency than fuel quality/detergents.

Sound like a plan?

 

The percentage of ethanol is going to have a bigger effect than ANYTHING else.

 

Plus, one tankful can be misleading. Keep a spreadsheet and record every fillup and driving conditions for the period.

 

Very true. Most every station around town here states that up to 10% ethanol is mixed in with gasoline.

 

I spoke with a local gas attendant the other day, he said that their gas has 10% (not up to 10%) Ethanol. I always set the pump on the lowest notch and let the fuel shutoff automatically. And, I attempt to use the same pump, at the same station every fill-up. It may not be completetly accurate but it makes me feel better.

 

What's the purpose of setting the pump at the lowest notch?

 

To reduce the air bubbles. More gas, less air in the tank.

 

The pump shuts off sooner when pumping fuel at a quicker rate vs. pumping fuel at a slower rate. Less to top off this way, at least with the pump's I've used.

I started doing this several years ago and haven't thought twice about it. Just something I do.

Thanks Bluejay...