PSI-FX4

Something sounds off. My stock EB Crew Fx4 with 3.73 gears easily pulled a truck from 0-80mph on a 2014 5.3L. I would imagine they didn't change that much from 2014 to 2015.
I raced another after getting a 87 octane tune several months later and it wasn't even remotely close.

I don't like to race mine either, but I love the look on a young kids face trying to act cool with his girlfriend in the truck with him (I used to be that guy, LOL). Most of the time they are not expecting a fight to be put up from a nasty work truck covered in mud. lol

Takeda

Motor Trend did a comparison of the Chevy with the 5.3L, F-150 with the 2.7L EB, and the Ram with the little diesel. As you can see from the numbers here, the EB walked all over the Chevy 5.3L:

dave91gt

I think something's off too but dealer says its normal. I have larger tires with 3.55's but he has a 3.08 gear.
Again, this wasn't a race per say. Just us merging onto the interstate.
Being the truck behind I at least know how hard I was in the throttle. It was somewhere in the inter cooler. I took it in for poor mpg and throttle delay a few months ago. They blamed the mpg on the tires and there were no codes so delay is "normal". The flag went up after buying our Expedition. I'm telling you it's like it already has a tune compared to the truck. Dealer won't do anything so I'm left to accept it or tune it.

Now I know how it should act and it makes me want the same out of the truck. It has no misfires, runs fine, etc. it has a good few seconds of black smoke on a cold start but no fuel smell in the oil. And it doesn't lose much if any oil between changes.
Researching tunes now. I don't want anything crazy. Just a nice bump that eliminates the mushy throttle response and lazy shifting. I also don't want to blow it up. That's the risk I know I face.

QwkTrip

I am not surprised you couldn't see much difference to the 5.3L in the situation you were in. It takes a whole lot of extra power, or a lot of time, to reel somebody in from behind at highway speeds. Especially when they get the jump by being in front of you.

The Ecoboost delivers a lot of low- and mid-range power but the turbos are small and it runs out of breath in the upper rpm's. Even a tune won't fix that. You can annihilate that 5.3L if you choose a situation where both engines spend more time in the low- and mid-range rpms..... like running from a stop, or towing heavy weight. And a tune will open up that gap by quite a lot. But you've just got to realize that freeway rolls are not the Ecoboost's specialty, tune or no tune.

violinguy77

Um, NO????? I don't know where to start with this no offense. A properly tuned EB will smoke any other stock truck all day long. Proof is in the pudding. I don't know of another single tune only truck (maybe a RCSB Hemi?) that can run the quarter mile in under 13 seconds.

https://www.f150forum.com/f70/ecoboo...2637/index126/

The chevy has an 8 spd tranny and that thing is pretty great when it comes to keeping the vehicle in the power band.

To the OP, you NEED the tune to get that truck back to where it needs to be. You are running a stock tune designed to operate in a stock configuration. You have added more rotating mass to the wheels, changed the final drive ratio, etc... Git r done and laugh while you watch his head lights get smaller and smaller in your rear view mirror.

Takeda

Sorry, the 2015 Chevy has a 6 speed tranny.

violinguy77

No apologies necessary Takeda, thanks for the correction! 8 speed is only available with the 6.2L configuration for 2015.

All the more reason to tune it and whip his ***** lol

130428

I'd say this guy nailed it. I'm sure your mate was pedal to the metal too, and it's not like the EB has that much more HP than the 5.3 that it would catch up instantly (think Porsche 918 vs Honda Civic situation!). So yes, not catching up is OK.
Having said that, nothing wrong with a tune, except that I like my 7-year ESP / FMPP

QwkTrip

It is quick... but it isn't fast. 1/4 mile trap speeds don't improve much on a tune. Most the improvement of 1/4 mile time is in the 0-60 mph sprint. The engine has air flow limits that won't let it build much extra top end torque, but a tune does wonders for low- and mid-range torque. That works really well when you're doing 0-60 mph sprints because you're moving through gears and the tachometer is quickly sweeping a broad range and doesn't spend much time above 5000 rpm. But once you hit those higher gears the tach sweeps slower and the engine ends up dwelling more at higher rpm where there isn't much difference to stock.

All I'm saying is the performance gap narrows significantly at higher speed. If you're scratching your head wondering why you can put 2 or 3 lengths on somebody from a stop, and then the same thing doesn't happen on freeway.... Well, now you know why.

violinguy77

Yea I get the bit about running out of breath on the top end. I have buddies with STIs and they had to do some significant mods to get more power on the top end but like you said that engine is only going to flow so much air. And I get what you mean about being quick vs. fast. The truck is certainly getting to speed much quicker.
Whats your best time on the LET tune and what mods are you running?
I love my 5.0 and it's potential, however I am pretty sure my next ride will be boosted. If I could find one for a reasonable price I would have a BMW535D in the driveway with a Burgur tune. My wife has an X5 35d and that mother is a freight train. I have read about guys breaking transmissions if they run the hotter tunes. But I digress, thanks for the discourse.