In the age of automotive downsizing...

If Nitrogen expands so much, why do racers use Nitrogen in their tires? Why do shock manufacturers use Nitrogen in shocks? It's because Nitrogen is thermally fairly stable.

 

I no more about NOX produced in automobiles than probably anyone ion this board, it’s a big part of what I do for a living. All I will say is a) I had NOTHING to do with dieselgate or any scandals b) a couple of you are about 50% right that being said there are obviously a couple intelligent people posting above (yes I said it).
As far as engines, size, etc. it’s really a messed up game with the epa/ CAFE standards. This is not about cheating the test, it’s about getting your fleet to x amount of emissions within that test criteria.
A fair amount of vehicles when driven somewhat sane see much better mileage, for example, than what’s on the window sticker. It’s a balance the OEM’s have to play and they all have slightly different strategies. Example GM went small with truck engines, well at least is giving it a shot with the 4 cyl. I’ve driven a few and shocked me how quick the truck was but even pushing it a little bit gets it out of its efficiency sweet spot and mpg drops off very fast. Ford went with large efficient and added some fancy stuff in there to pass the tests and still have a lot of potential to stay in its general efficiency range. If they can make the big motor work long term that’s awesome as far as I’m concerned. For a 150/1500 daily that rarely tows anything more than an open utility trailer (about 90% of the trucks) my personal well balanced motor is the eco boost 6 in the Ford. GM is trying to compete with that with the 4 and although it’s an impressive little motor I think they are just asking a lot from it. Would be like mongo racing 250. Sure you could build one with enough power to move him but that’s a lot of strain on that motor to last. The GM 4 did pretty well in its durability cycles but there’s still reason to be concerned if doing any more than a Saturday trip to Home Depot.
That’s all for the jet lagged rambling.

 

Because it doesn’t get that hot get molecules excited enough to want to party with other molecules. Not even at Daytona

 

Not too bad old man Hit the nail on the head with “hitching a ride”

 

This is more of a pocket protector fight

 

Nitrogen in tires and shocks is more about getting dry gas in. It is the moisture in the gas that expands at relatively low temps, not the nitrogen itself.

 

Didn't mean to overlook this...I got distracted.
Um, I don't know how much air weighs but I guess it could be looked up/figured out cuz it's what, 14.7 psi at sea level?

(I get your reference and still stand by it. I just left the part out where the air is pushing from all sides, not just into the bed.)

 

That's not to say it doesn't expand or contract with temperature changes. What "they" are alluding to is its purity...no oxygen (a corrosive) and no moisture.
Nitrogen also happens to be abundant and easy to separate from the other gases. You could just as readily use atmospheric air, provided it was "dry", and get the same stability but it would have a corrosive factor.

 

Ummm... you realize that peak fuel efficiency is probably not going to be achieved at the peak horsepower number right? In theory with enough variable valves and injector flow etc you could make an engine that's very fuel efficient at low RPMs and still makes tons of power... I bet you could get close to 100 mpg with a current 400 HP engine with the right gearing and test course if you maintained the right RPM.

 

I think he missed the part where I asked if any of us knew the conditions under which they were getting 100+mpg on 400hp. I also mentioned our 430hp car getting 33mpg going 70mph at 1500rpm. And, btw, that's on cruise control, uphill/downhill, east/west through PA for hours...not just some flat stretch. I think it's worth noting that cruise control does not deliver the best mileage in hilly terrain.
Tripling that fuel mileage? Ours could prolly be tuned for another 50% cruising on flat ground, getting us halfway to those 110+ mpg numbers but I doubt we'd be doing 70mph.
(On flat ground, at 55mph, I get better than 36mpg, and upwards of 39. Yes, a Corvette is an economy car. )

Designing an high-powered engine specifically for high fuel economy? Why not?

Back around 1980, I think it was HotRod magazine that did an article on building a V8 for fuel economy. They took an old 350 SBC and got 32 mpg...very impressive for the time. IIRC, it got between 250-300hp and over 300ft/lbs torque.
How did they do it? Simply. They started by blueprinting (with slight overbore to clean it up), then took off-the-shelf components, cam/intake/carb/headers/ignition, to top it off. Only specific equipment I remember is the Edelbrock Torquer and a 2bbl carb.

Here we are about forty years later...I wonder what kind of mileage they could pull from a current V8?
Oh, wait. Apparently, that's been covered at SEMA.

 

https://www.roadandtrack.com/new-ca...9/ford-super-duty-73-v8-engine-details-specs/

 

Just checked Ford's online “build and price” feature...

F-350 XL Supercab 4x4 dually, 8' bed and the 7.3 gasser.

Less than $50K optioned my way, meaning a bare bones SuperDuty gasser might/could be had for as little as $40K. I'm thinkin' $45K out the door optioned to my flavor.

Tow capacity for the above vehicle...
- 3.73 gears, 16,300lbs.
- 4.30 gears, 20,000lbs.

Payloads for above vehicle, ~5700+ and ~6700+ lbs.

Max payload is over 7000lbs for the regular cab 4x2!

For this, I think I can overlook the fugly fenders and I'd be more than happy to not own a new diesel.

 

That article could be summarized as, GM’s design makes more sense. We copied it...

 

Interesting thread. Beats the 'Plane on a Treadmill' one by a mile or twenty....

But it's got to be said that any motor that runs only to 33% efficiency has room for improvement.

Nitrogen being part of the work package is an interesting concept, we need Kevin Cameron on this board...

It certainly acts as an insulator to protect the metal surfaces, else, at 100% oxygen, the combustion chamber would turn into a melted puddle.