2023 Ram MPG Upgrades - Hemi E-torque

[BowDown]

It's right there in the pic - 6,193km or 3,848 miles. Look at your RPM when cruising, if it's hitting 2000 then the VVT is starting to open up and sucks more fuel. At 68mph I'm just under the 2k point and that's when I can hit 23mpg, as long as there is no strong headwind. Your 18mpg sounds like an average rating. My 23mpg is highway cruising only.

That's not how VVT (variable valve timing works). It simply retards or advances cam timing based upon the engines RPM, MAP and throttle position to broaden the power band. It does not alter the cams lift or cause more fuel to be consumed

 

[theblet]

I live in a bad area to live, it's called Massachusetts.
Highways are 65, most city roads are 25-40. It's rare to see anything 45-55 except parts of rt9, which has stp lights every mile or so across the entire state.


I guess I must be mistaken. I thought the AC was powered by electricity, the alternator or in this case the generator with it's belts.

Compressor is belt driven. The clutch is electric. When the clutch engages, it puts more load on the engine to turn the compressor.

When the clutch isn’t engaged the pulley just free wheels

 

[ThatAirRideThough]

Lighter tires or a lighter wheel and tire package helps every time you have to accelerate (turn) the wheel, especially from a stop--sometimes you can save 10 pounds a tire or even more on a wheel and tire combo. Rotational weight calculates out much more than static weight, so lighter wheels and/or tires can make a difference. Also, checking out the forums dedicated to HyperMiling can teach you some driving techniques that can net some good results.
Also, relieving restriction with intake and exhaust can help so long as you drive it easy. I'd also reach out to a good tuner like Saterra Tuning or one of the big truck tuners and see if they can net you some savings with an aftermarket tune. That's my two cents.
Also, 3.21 geared trucks tend to get 1mpg or more than the 3.92 trucks on the highway, sometimes closer to 2 mpg but the cost to buy the front diff and have the rear geared would likely negate the fuel savings, at least for the foreseeable future.

 

[23RAM]

I mean, I can go to Denver, fill up and stop in Sterling, Co and probably have better numbers.

How about a 540 mile round trip at 21.5mpg? Filled up at the Petro-Canada station before the highway ramp near my home, drove to destination, refilled at Petro-Canada near highway, back home and refilled again. Toronto to Cornwall and back cruising at 67 mph. 22 going there, 21 coming back averaged to 21.5, hand calculated.

 

[23RAM]

That's not how VVT (variable valve timing works). It simply retards or advances cam timing based upon the engines RPM, MAP and throttle position to broaden the power band. It does not alter the cams lift or cause more fuel to be consumed

I know how VVT works, and in fact it does indeed open the intake valve for a longer period (not more lift but duration) allowing more fuel/air mixture to increase power. I can hear the exhaust note change at 2k and my fuel consumption increases. I've tried cruising at 70mph, just 2-3mph faster than ideal but mileage drops off faster than the added speed can overcome distance = worse fuel economy. With my 3.92 gearing, the sweet spot is 50-68mph and keeping acceleration under 2k rpm. If I drive with a lead foot to hear the growl of the V8 (which I do from time to time) I get poor mileage as expected...when I moderate the throttle and use cruise control, I get decent mileage.

 

[Darksteel165]

With my 3.92 gearing, the sweet spot is 50-68mph

Wow, that is some sweet spot.

 

[HSKR R/T]

How about a 540 mile round trip at 21.5mpg? Filled up at the Petro-Canada station before the highway ramp near my home, drove to destination, refilled at Petro-Canada near highway, back home and refilled again. Toronto to Cornwall and back cruising at 67 mph. 22 going there, 21 coming back averaged to 21.5, hand calculated.

Still not 23mpg. But with only cruisibg at 67 mph, that's believable. I averaged 19.5 mpg driving from Omaha to Oklahoma City and that was with average cruising speeds 70-75mph

 

[BowDown]

I know how VVT works, and in fact it does indeed open the intake valve for a longer period (not more lift but duration) allowing more fuel/air mixture to increase power. I can hear the exhaust note change at 2k and my fuel consumption increases. I've tried cruising at 70mph, just 2-3mph faster than ideal but mileage drops off faster than the added speed can overcome distance = worse fuel economy. With my 3.92 gearing, the sweet spot is 50-68mph and keeping acceleration under 2k rpm. If I drive with a lead foot to hear the growl of the V8 (which I do from time to time) I get poor mileage as expected...when I moderate the throttle and use cruise control, I get decent mileage.

You clearly do not know how VVT works.
Cam duration is set, its ground into the cam and cannot be altered, you're dead wrong on this. VVT either retards the cam or advances it (cam timing), the cams duration cannot and is not altered in any way.
Your exhaust note changing is MDS, not VVT
Your fuel mileage decreases as your speed increases....wait for it, because you have 3.92 gears

Have a read

How Does Variable Valve Timing Work?

If we want a new generation of car enthusiasts to care about cars, it can’t hurt to explain how things actually work.

jalopnik.com

and more

https://www.motortrend.com/how-to/hrdp-0908-variable-valve-timing/#:~:text=Changing%20The%20Cam%20CycleThe%20most,a%20cam%20is%20the%20opposite.

On engines with the intake and exhaust cam lobes ground on the same billet, a VVT mechanism advances or retards the entire cam (intake and exhaust) equally. Although the lobe centerlines change in relation to top dead center, the lobe-separation angle (LSA, the distance between the intake and exhaust lobe centerlines) remains the same. LSA changes are only possible if the intake and exhaust lobes are ground independently (not on a common billet). Until recently, this required a DOHC (dual overhead cam) setup.
Generally, you'd want to advance a cam for more bottom end, higher vacuum, and better idle characteristics. Retarding a cam aids the top end. A typical production cam optimized for an advance/retard VVT system is usually ground with reduced overlap, with VVT retard dialed in as needed to maintain or enhance the top-end power.

The only exception to the above is Mahle's CamInCam technology which was only used in the 2007 Viper then died on the shelf

 

[23RAM]

You clearly do not know how VVT works.

Never said anything about the lobes or lift - if you don't believe air/fuel volume changes with VVT, then I'm done talking about it.

Your exhaust note changing is MDS, not VVT

That would be a neat trick since MDS does not kick in under acceleration, or while in gear limit, or while in tow/haul mode. And VVT does alter the exhaust note.

 

[23RAM]

Still not 23mpg. But with only cruisibg at 67 mph, that's believable. I averaged 19.5 mpg driving from Omaha to Oklahoma City and that was with average cruising speeds 70-75mph

Best I've achieved is 23.6 cruising on the highway at 68. Here in Canada we have very few 70 mph roads - 62 is our posted limit for my area and under 68 seems like the sweet spot for mileage with 3.92 gears so that works out well.

 

[BowDown]

Never said anything about the lobes or lift - if you don't believe air/fuel volume changes with VVT, then I'm done talking about it.

That would be a neat trick since MDS does not kick in under acceleration, or while in gear limit, or while in tow/haul mode. And VVT does alter the exhaust note.

Lol, you have no idea how VVT, cams, cam timing and valve events work. As to lobes or lift, I said d-u-r-a-t-i-o-n. You claim that VVT changes the duration, explain to me how a cam with ground in duration, ground in LSA, ground in retard (112°+3° for example is a 109° LSA cam) can change simply using VVT to advance or retard the cam.

VVT alters the exhaust tone? Exactly how does cam timing effect exhaust note? LSA and duration will change the exhaust note, retarding or advancing the cam will not and only moves the power band down (boosts torque) when it advances the cam timing and extends the power band (increases horsepower and extend the usable RPM range) when timing is retarded.

then I'm done talking about it.

You should be, both links I provided dispute everything you said

 

[6of36]

I know how VVT works, and in fact it does indeed open the intake valve for a longer period (not more lift but duration) allowing more fuel/air mixture to increase power. I can hear the exhaust note change at 2k and my fuel consumption increases. I've tried cruising at 70mph, just 2-3mph faster than ideal but mileage drops off faster than the added speed can overcome distance = worse fuel economy. With my 3.92 gearing, the sweet spot is 50-68mph and keeping acceleration under 2k rpm. If I drive with a lead foot to hear the growl of the V8 (which I do from time to time) I get poor mileage as expected...when I moderate the throttle and use cruise control, I get decent mileage.

It does not open the intake valve longer. The valves open and close by the grind of the cam. VVT only change the timing of the cams. What changes is lifters that drop out and come on. That's different than VVT.

 

[Benca101]

Has anyone actually had any luck with upgrades that make a difference in MPG?
I know the biggest factor is the driver, and I also know most cars may benefit from a throttle body spacer, cold air intake, tuner, and sometimes exhaust.
With all that said, has anyone actually installed anything and noticed a difference? Even if it was 3-5 different things that were installed to make a difference?

P.S. I know these are trucks and not cars or a prius.... but I have kids in travel sports and drive 40-50k miles a year so anything helps.

I'll share two things:
1. Even though the exhuast is hard to improve on (none of the cat backs add any power), I replaced my muffler with a borla. I drive the same roads all of the time, and after this one change, one stretch of road the MDS came on, and remained on, for the entire length of it. Never before. I think it just provided that much extra breathing room that the engine had more room. Only evidence is that the stock muffer is NOT see through. But the Borla, you can see light when looking through one end of it. did this make any difference at all in day to day driving? No. But maybe I use a dozen less gallons a year.

2. I got on the freeway once, talking on a con-call for work. I had to drive about 40 miles, so I reset the trip odometer (curious when the truck was newer). Anyway, since i'm distracted on the phone, I just sat behind a real truck with adaptive cruise control. He averaged between 50 and 60 mph. I got about 24 miles to the gallon, including when I exited and stopped at lights. I drive a Rebel with 392s and a hemi. If you back off of the throttle, you can get pretty good mileage. Otherwise, I'm lucky to get almost 18 on the freeway.

All in all, with towing a lot, I've long since given up on mileage in the same hopeless manner I've given up on my wife getting horny. Pie in the sky my man.

 

[theblet]

You probably had a tail wind on a smooth road and weren’t doing too fast so mds was able to kick on. I have a flowmaster muffler and it’s no different than before.


Also, Your mpg will go up on any vehicle if you draft behind a semi.

 

[Benca101]

You probably had a tail wind on a smooth road and weren’t doing too fast so mds was able to kick on. I have a flowmaster muffler and it’s no different than before.


Also, Your mpg will go up on any vehicle if you draft behind a semi.

lol, do I seem that dense?
I hope not, had to make the wife joke.
1. Drafting a semi well requires a ridiculously unsafe distance. I had adaptive on the number 3 setting, which is hundreds of feet, I did this to lower the throttle oscillations and to prevent the brake slam when a californian female cuts you off. No semi, cruise set at 55 mph? I tested it, and yeah, low 20s for mileage consistently.
2. I know my local roads, I even know the local weather, sorry your flowmaster isn't a borla. ;-P

 

[23RAM]

It does not open the intake valve longer. The valves open and close by the grind of the cam. VVT only change the timing of the cams.

I didn't mean to say it opens the valves for longer periods, it alters the timing with the piston travel to increase/decrease intake flow - the duration where more fuel/air intake can occur. I guess my wording about duration wasn't precise enough for some.

 

[HSKR R/T]

lol, do I seem that dense?
I hope not, had to make the wife joke.
1. Drafting a semi well requires a ridiculously unsafe distance. I had adaptive on the number 3 setting, which is hundreds of feet, I did this to lower the throttle oscillations and to prevent the brake slam when a californian female cuts you off. No semi, cruise set at 55 mph? I tested it, and yeah, low 20s for mileage consistently.
2. I know my local roads, I even know the local weather, sorry your flowmaster isn't a borla. ;-P

You don't have to be dangerously close to benefit from drafting a semi. Mythbusters did an episode. Even at 100' behind the semi, there was still some benefit to fuel consumption.

 

[PurpleRT]

All that just to hopefully get another extra mile of mpg if that. No thanks let them wild cowboy truck drivers get as far away from you.


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[HSKR R/T]

All that just to hopefully get another extra mile of mpg if that. No thanks let them wild cowboy truck drivers get as far away from you.


Sent from my iPhone using Tapatalk Pro

My displayed instant fuel mileage is usually 2-3 mpg higher drafting a truck vs when I pull out and get in front of them.

 

[Dewey]

You don't have to be dangerously close to benefit from drafting a semi. Mythbusters did an episode. Even at 100' behind the semi, there was still some benefit to fuel consumption.

Yep. I've tried that but gave up very quickly since I cannot drive that slow. Not to mention driving 20,000 miles/year on interstates I learned very early on to never hang out near semi's. Get away from them as quickly as you can. First time one lets loose a blown tire or retread and it bounces off your hood/windshield you tend to learn.

I'll be the guy flying by semi's in the left lane getting 1-2 mpg less.