To floor it or not to floor it (yeah this is about MPG)

[Cliffrunner88]

Yes it’s a truck, and yeah I have the 3.92. And now that we got that out of the way…lol.

So I accidentally had left my screen on the fuel economy when I was flipping through at a light and I realized that if I try to accelerate slowly to save some gas (still getting 5-7 mpg), it takes me a good while to get up to speed where I can cruise in ECO and get those mpgs up. OR, I can punch it, get 3-4 mpg, but get up to speed in a much shorter distance and cruise further.

Therefore, back to the question: to floor it or not to floor it?

 

[Scap]

In my mind, as long as you're not getting tire spin, you're probably looking at similar fuel consumption. My theory is that you're doing the same work moving a brick from a stand still to some cruising speed where the transmission can shift into overdrive.

One version is long and slow. The other is short and quick. But both get you to 8th gear.

Where my theory falls apart is that wind resistance, friction, heat generation, engine inefficiencies, and on screen calculation errors are not taken into effect.

TLDR; I don't know the answer.

 

[Mountain Whiskey]

 

[JoeCo]

Floor it...for the sake of those driving behind you. I can't stand being behind people trying to hyper mile (it's one thing on the highway if people stay out of the passing lane and you are able to get by them) and not being able to legally get by them.

That's my only take on it, too many times being stuck in a huge line of cars because someone crawls away from each traffic light and then can barely get to 30. To be fair, I don't always know if this is someone hyper miling, or if it's someone who's about 100 years old that probably shouldn't be behind the wheel any longer.

My opinion may be in the minority here, at least it seems to be in my local area that is just full of slow drivers (or maybe I'm too fast?)!

 

[Richard320]

My gut feeling is a reasonable acceleration up to speed is better than oozing up. I base this on watching that economy screen. Seems like whether I accelerate like a normal person or some eco-warrior hyper-miler the screen still shows about 6 mpg instantaneous. So the less time/distance spent at that consumption, the better. If you have to alert everyone that, "Yeah, it's got a hemi," all advice is off.

 

[jkm312]

Just drive it, be reasonable. 7100 lbs of momentum does not stop as easily as a lighter weight vehicle. For whatever the reason when you rear end the vehicle directly ahead of you, your it. Cop doesn't care one wit what your reasoning was. People do all kinds of stupid stuff in traffic these days. In my 50 years of driving, I've driven everything from semis to Harleys. There is nothing more frightening than not knowing for sure if you are going to get stopped because of something that you had nothing to do with in front of you, but you have to get stopped. I always managed . . . . . . . somehow.

I'm reasonably sure you don't fit into the above category. Once in awhile we all have to punch it, on ramps, passing, and to get out of the way. It's just the way it is.

Once in awhile when you are all by yourself pulling out on a straight stretch of highway, it's just plain fun to lite her up and let her go. It does both the truck and myself some good.

 

[Trippi]

Floor it...for the sake of those driving behind you. I can't stand being behind people trying to hyper mile (it's one thing on the highway if people stay out of the passing lane and you are able to get by them) and not being able to legally get by them.

That's my only take on it, too many times being stuck in a huge line of cars because someone crawls away from each traffic light and then can barely get to 30. To be fair, I don't always know if this is someone hyper miling, or if it's someone who's about 100 years old that probably shouldn't be behind the wheel any longer.

My opinion may be in the minority here, at least it seems to be in my local area that is just full of slow drivers (or maybe I'm too fast?)!

Agree...get GOING!

 

[jdmartin]

Neither. For maximum fuel economy you generally want to be at the lowest speed in the highest possible gear, because what you are aiming for is the lowest possible ratio for the maximum amount of speed at that ratio at the lowest possible engine rpm, everything else being equal. So I think the final Ram drive for the 3.21 is .67. So maximum fuel economy is going to be more or less the top speed that can be maintained there without downshifting. On my Titan top fuel economy in a flat area was about 45-50 MPH, which was about 2k RPM in 5th gear. With 8 gears it might be 55-60, I haven't really checked. As for getting there, if you floor it you will overshoot the shift points, thus wasting some fuel, and if you crawl it you will spend unnecessary fuel in less economical power bands.

So accelerate normal and you should be good

 

[BlackBeauty14]

Ive found, by watching the instant mpg readout on the dash, that when it comes to mpg's, it matters more on how far down you are pushing on the gas pedal than it does the number of rpms the engine is spinning. In other words you can be better off one gear lower and turning higher rpms, than a gear higher and turning lower rpms if it takes pressure more on the throttle to maintain your current speed.

 

[theblet]

I kind of do the latter. Doesn’t matter if I take off slowly or quickly, im making 3 to 4 mpg either way. So i rather take off a little quicker, have the shift come around 3 to 4 rpm. Then I get to the desired speed quickly and set the cruise. I usually manage to get around 18 mpg avg with a lot of city driving and idling.

 

[mmcbeat]

I put my foot in it when I drive. It is ”throttle by wire” so there is a built in buffer that prevents you from taking full advantage of the fuel injectors when taking off.

 

[5thGenLoco]

Traction control "off," 15-20 feet of burnout, enjoy your hemi

 

[Mountain Whiskey]

Traction control "off," 15-20 feet of burnout, enjoy your hemi

Went fishtailing out into the road just the other day. Darn traffic.....

Anyway, I will add my nickle since inflation has hit so hard this year for some strange unknown reason ...
We have injectors controlled by a computer reading multiple sensors that squirt fuel to mix with incoming air. The injectors must keep the fuel/air ratio at the optimum mixture so it does not run lean and damage the engine or run rich an (oh the horrors) damage the environment. So if you are flooring it or babying it, the ratio of fuel to air should be similar shouldn't it?

If all things were equal it would not matter as we all know for each action there is an equal opposite reaction. So if the drive train operated at the same efficiency, the same energy would be expended. How to figure if that holds true? I don't know. I hire people to figure crap like that out for me at work.

 

[Cliffrunner88]

Went fishtailing out into the road just the other day. Darn traffic.....

Anyway, I will add my nickle since inflation has hit so hard this year for some strange unknown reason ...
We have injectors controlled by a computer reading multiple sensors that squirt fuel to mix with incoming air. The injectors must keep the fuel/air ratio at the optimum mixture so it does not run lean and damage the engine or run rich an (oh the horrors) damage the environment. So if you are flooring it or babying it, the ratio of fuel to air should be similar shouldn't it?

If all things were equal it would not matter as we all know for each action there is an equal opposite reaction. So if the drive train operated at the same efficiency, the same energy would be expended. How to figure if that holds true? I don't know. I hire people to figure crap like that out for me at work.

What is it you do?

 

[Mountain Whiskey]

What is it you do?

Do for what?

 

[Cliffrunner88]

Do for what?

For work. You said you hire people to figure stuff out like that for you.

 

[Mountain Whiskey]

For work. You said you hire people to figure stuff out like that for you.

Oh, sorry, I was not thinking. I am a director at an engineering firm for the construction cost engineering department. I hire engineers to figure out the formulas then correct them.

 

[jdmartin]

Oh, sorry, I was not thinking. I am a director at an engineering firm for the construction cost engineering department. I hire engineers to figure out the formulas then correct them.

Which one? Aren't you in Asheville? I might know you or at least your firm

 

[Mountain Whiskey]

Which one? Aren't you in Asheville? I might know you or at least your firm

We are right here in the DC area.

 

[jdmartin]

We are right here in the DC area.

Aha. I don't know why but I thought you were down here. Maybe it was the mountain name...