Atkinson motor and fuel octane

[Darnon]

I was under the impression that Atkinson engines change the compression ratio, through some rocker joints underneath the piston, allowing the pistons to have a higher or lower top dead center.

There's engine that do the whole variable stroke mechanics like you're describing, but an Atkinson cycle can be achieved just with variable valve timing.

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[ProDigit]

2.5L/162-hp/155-lb-ft Atkinson-cycle DOHC 16-valve I-4, plus 126-hp/173-lb-ft electric motors. Yep, they only publish the combined HP. I think the line of thinking still applies. electric on the low end; engine comes to the party later in the revs. I would like to see actual HP/torque curves

It is entirely possible that the motor is an 80HP motor, paired with a 40HP motor/generator, giving a combined output of ~120HP on the electric side.
That being said, electric motors usually have a 3,5k RPM limit, half of an engine, and their peak torque is like between 500-1000RPM. Which usually means in that RPM range, they can easily have 100-300LB FT of torque for a 100HP rated motor under normal operation, much like what most engines have under high RPM.

The output of electric motor/engine is like you describe in eco mode.
In normal mode, the motor pushes the car to <5MPH before the engine is already aiding the motor in acceleration.

 

[BMCGC]

assume 25MPG EcoBoost vs 35MPG Hybrid driven 15,000/yr, well the Hybrid still saves money even if that Hybrid driver pays for premium. Run the #s yourself to see. So these arguments about premium being a moneypit get thrown out the window with these MPG gaps. The biggest savings is much better MPGs -- not low grade octane. If I get a slight efficiency boost in a Hybrid, good; but the big savings isn't from which fuel I pump but how much I pump.

Comparing an EB to a hybrid is comparing apples to oranges.

The real number is cost of ownership.

Operating cost is a part of the cost of ownership calculation.

My local prices are $3.47/P and $2.97/R, a difference of 17%.

Will using P fuel give me 17% better fuel mileage in my vehicle than using regular fuel?

If the answer is no, then I am increasing my operating cost and my cost of ownership.

 

[Larrythelunatic]

Comparing an EB to a hybrid is comparing apples to oranges.

The real number is cost of ownership.

Operating cost is a part of the cost of ownership calculation.

My local prices are $3.47/P and $2.97/R, a difference of 17%.

Will using P fuel give me 17% better fuel mileage in my vehicle than using regular fuel?

If the answer is no, then I am increasing my operating cost and my cost of ownership.

Thanks guys,
It’s 0300-0500. Can’t sleep.
Checking the “What’s new”.
Ran into one of the more fascinating threads on the site!
Nope……didn’t put me to sleep. Quite the opposite!
Keep this stuff coming, please.
At least until my Mav is coming………

 

[BMCGC]

I woke up at 4am eastern time.

Read the news
Checked the sports
Looked at the bank account
Looked at CL for Harleys and Mustangs
Looked at FB
Looked at this site

About to put a big egg white omelet with all the fix n's in the oven.

 

[Krrr]

Change the clock. Fall back.

 

[Skisail]

I don't know anything about the science or any of that other stuff you smart people talk about. I have a 2021 Lexus ES300h Ultra Luxury auto with a little over 3,300 miles. The Dealer filled the tank with 87 Octane when I purchased the vehicle. I have ONLY put Pure's Ethanol Free fuel in the car since then. There Ethanol Free is 89 Octane and we won't discuss the price increase since January 20th 2021. Anyway, here is a screen shot of my Fuelly App. I'll let the numbers speak for themselves. I can only pray the Maverick can do the same.

Somethings off here. 3303 miles divided by 88 gallons is 37.5 MPG. Good, but not 44.0 MPG.

 

[Atisko]

The problem with corn is that it requires crop rotation and a lot of resources like water and pesticides. The best way to make a natural based fuel would be with hemp. Grows like a weed (pun intended), grows in tons of biomes, no pesticides, no crop rotation, it cleans soil…and is extremely versatile. Ok end rant on future petroleum ideas

Corn is awful for people in the environment for a lot of dynamic reasons..,,

 

[mamboman777]

Ethanol is really stupid. Who on earth came up with the idea "hey, let's burn the food?"

You say that, what I wish they'd do is use the husk and cobs to make ethanol. Might get less, but that stuffs just being thrown away.

 

[BMCGC]

You say that, what I wish they'd do is use the husk and cobs to make ethanol. Might get less, but that stuffs just being thrown away.

Not really.

Most factories are zero landfill or working toward zero landfill.

The husks and cobs end up being animal food.

At Frito Lay, all the potato peels go to hog farms. Water is used to clean and move the potatoes into the fryer. The water turns white from starch. The starch is recovered and the water that goes into the sewer system is as clean as the water out of the tap.

Even pineapple cores and skins get recycled into animal feed.

 

[mamboman777]

Not really.

Most factories are zero landfill or working toward zero landfill.

The husks and cobs end up being animal food.

At Frito Lay, all the potato peels go to hog farms. Water is used to clean and move the potatoes into the fryer. The water turns white from starch. The starch is recovered and the water that goes into the sewer system is as clean as the water out of the tap.

Even pineapple cores and skins get recycled into animal feed.

Good to know! Thank you! Glad we're doing everything we can.

 

[BMCGC]

I would like to believe that zero landfill is out of concern for the environment, but is is all about profit margins.

15 years ago I worked in a plant that threw away a giant amount of plastic wrap. I asked the manager why we didn't sell it instead. He had never even thought about it. 3 months later we were compressing and banding it. We had about 2 semi loads a month going out. The result was a reduction in landfill fees and my boss got a nice bonus.

 

[STARCOMMTREY1]

I would like to believe that zero landfill is out of concern for the environment, but is is all about profit margins.

15 years ago I worked in a plant that threw away a giant amount of plastic wrap. I asked the manager why we didn't sell it instead. He had never even thought about it. 3 months later we were compressing and banding it. We had about 2 semi loads a month going out. The result was a reduction in landfill fees and my boss got a nice bonus.

We did the same thing with our metal scraps. Lowered our dumpster fees and bought a trailer we modified. It brought about 500 per load. We used that to do things like crawfish boils for the company.

 

[fbov]

I was under the impression that Atkinson engines change the compression ratio, through some rocker joints underneath the piston, allowing the pistons to have a higher or lower top dead center.

You're thinking of the Nissan VC turbo. Atkinsons use intake valve timing to vary the intake charge from 90% down to 50% fill, without changing the stroke at all.

That being said, electric motors usually have a 3,5k RPM limit, half of an engine,

That's typical of the "torque converter replacement" hybrids. This Ford's motors redline more like 18,000 RPM. Think router motor, not a cordless drill.

 

[Dbarr]

I drove a 2010 Fusion hybrid (similar engine) for 140,000 miles and never once put premium in it and it was fine. Mileage was good as well - over 40 in city driving, 37 highway.

Similar store with 2007 Camry hybrid with 370k… I did get better mileage with 100% gas, but I cannot say if it is worth the extra cost over 10% ethanol

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