Maverick Hybrid climbing hills / 10% grade ?

[JASmith]

Please consult an actual authority, like Sears & Zemansky. F=ma all day, every day.

Force at the wheels, and we are talking about force over time, or work. Its explained in the video with all the equations and a lot of math done to break it down into bite sized chunks, and you can't oversimplify and pretend you have an understanding of the physics involved by ignoring half the factors at play. But if you want to remain ignorant, I can't really help you. Just know that spreading misinformation does everyone a disservice.

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[Probity]

The Maverick was certified with SAE J2807, aka Davis Dam, which is the same certification that Super Duties and all pickup trucks go through in the US. The test involves way more than a 10% grade, for a long time, in the heat, with the A/C on blast, and towing some amount. 10% should theoretically be a piece of cake if you’re not towing anything, and doable even if you are..

Almost true. Regardless, OP should be fine with the Hybrid.
1. Davis Dam test speed requirements probably less than OP is thinking about, just don't plan on cruising at 70+ mph effortlessly for miles up a 10% grade based on J2807 performance.

2. Davis Dam run fairly long, but not a 10% grade.

 

[Probity]

Jessica is correct. It's more than opinion.

The above is another reminder that the old saying is true:

Arguing with a (fill in your particular discipline) engineer is like mud wrestling with a pig....everybody gets filthy and the pig loves it.

 

[lb1998]

So, as a lady with zero understanding of all this, is the answer yes or no? Will my Hybrid climb a 10 percent grade with no problem? "Check YES or NO"

 

[r100gs91]

Yes

 

[Big_T]

So, as a lady with zero understanding of all this, is the answer yes or no? Will my Hybrid climb a 10 percent grade with no problem? "Check YES or NO"

The simple answer is Yes.
https://www.mavericktruckclub.com/f...ybrid-climbing-hills-10-grade.3947/post-83874

 

[fbov]

Remember, force at the wheels is what matters, ... Here's a bunch of math and number crunching to prove it, but if you just want to skip to the end as he says, "Maximum acceleration at any speed happens when the engine is delivering maximum horsepower, if anyone tells you this occurs at peak engine torque they are BSing you."
(media deleted)

Two can play this game, something I'll do once. You should have listened at min. 4:05:
"So, for maximum acceleration of the car at any snapshot in time, we need to maximize the torque at the driving wheels."
As someone said, F=ma, all day, every day.

He starts into the weeds at min. 8:18, rescues everything at 9:18, and then ignores that, and dives back into power-love. His example is specious; without a turbo and aggressive waste gate management, you don't get a flat torque curve with no discernable peak, and his had waving at the end falls apart. Too bad he's BSing you in the quote above, even though he knows better. Makes this clickbait.

His mistake? He points to the wrong number... even though he knows better!

For the record, power matters when trying to balance motive power against parasitic losses, like drag and rolling resistance. RR is trivial, with only a slight increase with velocity, while drag force varies as velocity^2, so drag power varies as velocity^3. To double speed, you need 8x the power. That's why drag coefficient, Cd, and engine power, are so critical to top speed.

 

[JASmith]

Two can play this game, something I'll do once. You should have listened at min. 4:05:
"So, for maximum acceleration of the car at any snapshot in time, we need to maximize the torque at the driving wheels."
As someone said, F=ma, all day, every day.

You keep ignoring the point that its torque at the driving wheels that matters and that horsepower is a function of torque production. You don't seem to comprehend why I keep talking about the importance of the transmission.

Maximum torque at the wheels for any given speed occurs at maximum horsepower. He even did all the math for you in each gear to demonstrate this. I can only surmise at this point that you feel too entrenched in your position to admit you were wrong, which wouldn't be a big deal in and of itself, but being on a public forum it just contributes to more ignorance if not addressed.

To put it bluntly, its making everyone dumber for having read it.

If you don't want to get bogged down by the math of it, use common sense. If maximum acceleration occurred at peak torque for any given speed, then CVTs would be designed to hold RPMs at peak torque rather than peak horsepower when attempting to achieve maximum acceleration. Are the automotive engineers all clueless holding buzzy high RPMs if its not only higher NVH but slower to boot? Of course not. If that is still too confusing, lets look at manual transmissions.

The Volkswagen GTI achieves peak torque of 258 ftlbs @ 1,500rpm
Source: https://www.caranddriver.com/volkswagen/golf-gti-2021/specs

If peak acceleration occurs at peak torque, then logically you would want to shift into second gear before 2,000rpm, and ditto for third and fourth gears and so on.

I think you will notice that the VW is accelerating MUCH slower at 1,500rpm torque peak at say 30mph in 4th gear than it does at around its 5,000rpm horsepower peak in 1st gear at the same 30mph speed. What is happening? Torque multiplication. Torque multiplication is highest the lower the gear you are in, right? So then if that's the only thing that matters then why would you not necessarily want to upshift far past your peak horsepower? Bingo, because despite a higher torque multiplication potential, the torque per minute output (horsepower) has dropped too much, and maximum acceleration for any given speed occurs at peak horsepower.

 

[fbov]

Maximum torque at the wheels for any given speed occurs at maximum horsepower. ...

You said it, I didn't. Please take your own advice.

 

[JASmith]

You said it, I didn't. Please take your own advice.

I said what specifically? You are completely oblivious to the difference between engine torque and wheel torque and seemingly what horsepower is. Maximum torque at the wheels does not occur at peak engine torque in a vehicle with a CVT (or really any transmission). The wheels, or tires if you want to be specific, are the interface that drives the vehicle forward. Peak torque at the wheels occurs at peak engine horsepower for any given speed due to gearing.

If you need more detailed equations, see: https://engineering.stackexchange.c...cceleration-of-a-car-from-rest-optimum-launch

Therefore, to maximize acceleration at any given speed, we need to maximize engine power (which is the same as wheel power, ignoring losses due to friction). This result has important theoretical implications. First, it proves that, although the peak engine torque number is essentially meaningless, the peak engine power number is actually enough to, theoretically, calculate the maximum possible acceleration the car can achieve at any given speed. So it sort of ends the age-old "power vs. torque" debate.

A better analogy than I have been able to come up with is posted further below:

Imagine hitting a punching bag with a baseball bat as hard as you can. It will barely move, but with the same force gradually applied you can move it further.

The second thing to note is that power is the rate at which the engine is generating energy, measured in Watt. 1 Watt is 1 joule per second, and a Joule is the energy needed to move 1 newton a distance of 1 meter (Nm, but not to be confused with torque, which is just a rotational force).

Although your peak power is at a point where the torque is below peak, you are adding energy into the system more quickly, thus "distance increases more quickly" i.e. you accelerate faster.

Imagine hitting the punching bag repeatedly with full force; it will move further and faster with each hit. Now imagine decreasing the force a bit, but hit it more quickly, you'll burn more calories and move the bag quicker.

Note that while the above indicates power is measured in watts, that's simply the SI unit of power whereas horsepower is an imperial unit... same thing, like kilograms vs pounds.

 

[fbov]

Seriously?? This is your authority?
" I have a background in math, but I'm no expert in engineering or physics. ..."

Algebra errors in the first equation, and the second reduces to accel = torque / mass (F=ma). He's at least honest enough to admit there are limits to his understanding.

Ignoring the detail issues, the problem may be that you don't see that problems in physics can usually be solved multiple ways. In this case, Force, Energy and Power can be used interchangeably to solve these kind of problems, because you can always convert among them.

The idea is to use the approach that provides the most insight into the desired way forward. I drank the HP Kool-aide like everyone else, until I did some modeling, As an autocrosser, HP didn't matter.

 

[02ST]

So, as a lady with zero understanding of all this, is the answer yes or no? Will my Hybrid climb a 10 percent grade with no problem? "Check YES or NO"

I think this is a valid concern and a good question. The hybrid is purpose-designed to draw peak power demands from the battery, allowing for an ICE tuned for high efficiency at the cost of lower ICE power. The battery can supply power for only a limited amount of time, the biggest usual demand I think is accelerating from a stop, after which cruising on lower power but for a long time is taken up by the ICE. So your question really asks how the ICE performs when the battery energy is depleted, in your example from going up an assumed long steep grade.

One problem is that "with no problem" might mean different things to different people.

I think the easiest way to get an answer to your question is to wait until the hybrids arrive and watch some real-life tests. Then you can tell if the ICE strains more than you would like in this situation, and if the benefits of the hybrid outweigh your concerns.

<Edit> Member Big_T posted a link to a video where a hybrid Maverick tows a trailer up a 7% grade. This is similar to your question about performance on a 10% grade.

https://www.mavericktruckclub.com/f...averick-towing-capability-tested-by-tfl.4884/

 

[MakinDoForNow]

So, as a lady with zero understanding of all this, is the answer yes or no? Will my Hybrid climb a 10 percent grade with no problem? "Check YES or NO"

I expect it would easily without a trailer but you might run into trouble when the electric drive motor runs out of battery and if the ice cannot do it on its own. Sorry about yes& no answer.

 

[Delbert]

Yes.

I have a paved driveway which is a 1/4 mi long and 23% grade in one section. Most of it is over 20%. My wife's Honda Hybrid Accord does it no problem. Even if you stop in the middle, it will start just fine. The electric motor has all kinds of low end torque and it is smooth. The secret is the front wheel drive.

RWD pickups on the other hand get stuck if they stop. Even my F150 work truck with a big ecoboost engine and a/t tires needs to be put in 4wd to get going if it gets stopped on the hill. This is why I will not buy a traditional 2wd pickup. I am buying a Hybrid Maverick.

My Subaru Forester with AWD and a CVT does fine. Last week, I had 2,000 pounds of gravel in a trailer and the Forester found a low gear I did not even know it had and it chugged right up the hill. I did worry if it had a gear low enough. It is only rated to tow 1,500 lbs.

Long hills with grades over 10% a couple of miles long will deplete the battery. Fortunately, there are not many of them around. The Ford ecvt retains some battery power even when climbing a hill so you can floor it and pass a vehicle even after some sustained hill climbing. The Atkinson cycle will keep delivering power as shown by by the TFC video. Whether or not it is a good idea to do it on a daily basis is another story.

The hybrid delivers torque when you need it. The torque curve is controlled by a computer and can be modified using the drive modes. I think it is a versatile drivetrain.

 

[TacoHolder]

Took my 4 cylinder Tacoma (very similar power specs to Mav Hybrid) up 6% grade at 6000ft+ elevation a few wekends ago. It will climb at highway speed, but it's definitely a struggle. It's actually why ended up ordering a EB AWD just yesterday.

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