Have our trucks got too much power yet?

[4x4ord]

I've often thought about all the energy being wasted with braking applications and exhaust braking on down grades. It's only a matter of time before our rvs will have electric drive axles to help hold back on the down hill while charging a battery pack so the energy can be used to help push us up the up hill sections of our journey. Instead of having 500 hp under the hood we could get by with a more fuel efficient 300 hp diesel and have another 200 hp available at our trailer axles.

[Bedlam]

I think Mazda has a better method:

https://www.roadandtrack.com/car-culture/a17171105/mazda-skyactiv-x-how-it-works/

[4x4ord]

wilber1 wrote:

4x4ord wrote:
I cant think of an application where two different displacement turbo diesels are offered in the same vehicle but the Honda Accord Sport is available with two different turbo gasoline engines of different displacement and I know the smaller engine is rated to get somewhere around 10 - 15% better fuel economy. It seems to me the Honda engines are both designed to make similar power per liter. In the example I'm talking about .... a 6.7 making 475 horse vs a 5.0 making 300 I would expect a greater spread in the low load fuel economy than in the Hondas case because the 5.0 liter can be designed with a higher compression ratio than the 6.7.

Nissan's variable compression ratio engine does both. Low compression/high boost for power, high compression/low boost for economy.

I hadn't heard of that engine so I was quite interested in finding out more about it. Unfortunately this is what I found out.

[4x4ord]

FishOnOne wrote:

rjstractor wrote:

FishOnOne wrote:

FlatBroke wrote:
Too much power

I'm sure the turbos are still good. :E

The driver's shorts, not so much....

LMAO... I didn't think about that one. :B

Wow. I've heard one go through the fan but never have I seen a cat jump out from under the hood like that before.:)

[4x4ord]

Oops

[FishOnOne]

rjstractor wrote:

FishOnOne wrote:

FlatBroke wrote:
Too much power

I'm sure the turbos are still good. :E

The driver's shorts, not so much....

LMAO... I didn't think about that one. :B

[rjstractor]

FishOnOne wrote:

FlatBroke wrote:
Too much power

I'm sure the turbos are still good. :E

The driver's shorts, not so much....

[FishOnOne]

FlatBroke wrote:
Too much power

I'm sure the turbos are still good. :E

[wilber1]

4x4ord wrote:
I cant think of an application where two different displacement turbo diesels are offered in the same vehicle but the Honda Accord Sport is available with two different turbo gasoline engines of different displacement and I know the smaller engine is rated to get somewhere around 10 - 15% better fuel economy. It seems to me the Honda engines are both designed to make similar power per liter. In the example I'm talking about .... a 6.7 making 475 horse vs a 5.0 making 300 I would expect a greater spread in the low load fuel economy than in the Hondas case because the 5.0 liter can be designed with a higher compression ratio than the 6.7.

Nissan's variable compression ratio engine does both. Low compression/high boost for power, high compression/low boost for economy.

[FlatBroke]

Too much power

[valhalla360]

4x4ord wrote:
I cant think of an application where two different displacement turbo diesels are offered in the same vehicle but the Honda Accord Sport is available with two different turbo gasoline engines of different displacement and I know the smaller engine is rated to get somewhere around 10 - 15% better fuel economy. It seems to me the Honda engines are both designed to make similar power per liter. In the example I'm talking about .... a 6.7 making 475 horse vs a 5.0 making 300 I would expect a greater spread in the low load fuel economy than in the Hondas case because the 5.0 liter can be designed with a higher compression ratio than the 6.7.

You see it a lot in boats and assuming you don't use those extra horseys, they difference is typically to small to measure.

[4x4ord]

I cant think of an application where two different displacement turbo diesels are offered in the same vehicle but the Honda Accord Sport is available with two different turbo gasoline engines of different displacement and I know the smaller engine is rated to get somewhere around 10 - 15% better fuel economy. It seems to me the Honda engines are both designed to make similar power per liter. In the example I'm talking about .... a 6.7 making 475 horse vs a 5.0 making 300 I would expect a greater spread in the low load fuel economy than in the Hondas case because the 5.0 liter can be designed with a higher compression ratio than the 6.7.

[valhalla360]

4x4ord wrote:
^^^^ You may be right that the difference in mpg cruising down the highway might not be "that much". It would probably be 10% and overall mileage would be affected by about 15%. So in my case if I owned a smaller engine truck for 10 years I could expect to save $5500 .... I don't think it would pay for the electric axles I would want on my RV if I had the smaller engine.

Going from 5.0l to 6.7l in the same truck...I would be very surprised if there was a 10% improvement. I'm thinking more like 2-3%...maybe none.

Even empty both engines are far enough into their power bands that efficiency won't be greatly different.

[larry_barnhart]

rhagfo wrote:

winniman wrote:

rjstractor wrote:

wilber1 wrote:

Cummins12V98 wrote:
"I live in a place that has the highest gas prices in North America but relatively cheap electricity. I am seriously considering a PHEV as my next vehicle."

YEA but think about all the Salmon you will be killing.

Why? the two main salmon rivers are the Skeena and Fraser. They don't now, nor will they ever have dams on them.

BC gets about 90% of its power from hydroelectric-from the Columbia and Peace rivers. The BC power from the Columbia doesn't harm any salmon- because the dams downstream in the states take care of that... all joking aside, it's too bad we can't (or won't) develop hydroelectric technology that allows for fish passage. Hydro power is literally solar energy.

I have been to the Bonneville Dam in the Columbia Gorge. They have fish ladders for the fish to get around the dam.

Yes, several of the dams on the lower Columbia have fish ladders, but there isn't one on the Grand Coulee dam that I know of.

That would be something to see if it was built.

chevman

[Cummins12V98]

winniman wrote:

rjstractor wrote:

wilber1 wrote:

Cummins12V98 wrote:
"I live in a place that has the highest gas prices in North America but relatively cheap electricity. I am seriously considering a PHEV as my next vehicle."

YEA but think about all the Salmon you will be killing.

Why? the two main salmon rivers are the Skeena and Fraser. They don't now, nor will they ever have dams on them.

BC gets about 90% of its power from hydroelectric-from the Columbia and Peace rivers. The BC power from the Columbia doesn't harm any salmon- because the dams downstream in the states take care of that... all joking aside, it's too bad we can't (or won't) develop hydroelectric technology that allows for fish passage. Hydro power is literally solar energy.

I have been to the Bonneville Dam in the Columbia Gorge. They have fish ladders for the fish to get around the dam.

They do but you really think they all get thru???? NOT hardly.

Why do you think the GREENIES that push Electric cars want the Dams removed? They claim the Dams KILL Salmon.