Define "working hard." IMHO any motor has to work the same amount to move a given machine, with a given load, at a given speed on the same terrain. And with CVTs it'll always be doing that near peak-HP RPM when the load gets high. I don't see how the NA 4-banger works any less than a turbo 2 Cyl to produce the same result.
So your going to sit there with a straight face and say for instance that a YFZ450R works just as hard as a 700 Raptor to move the same 250lb rider and bike. You are also saying that a LS1 N/A pushing a 2 seat funco is going to work just as hard as a 4 banger subie with a turbo pushing the same car.
And you're going to sit there "with a straight face" and pretend you read my post at all? Try again, I'll give you the pertinent part:
The thing is, with a CVT that standard just doesn't apply. They jump to peak HP RPM nearly instantly when you get on it, and are using HP the whole way. What you're thinking about applies more to traditional transmissions where you need torque to get you from <launch RPM> to 5k+ where HP takes over.
Where are you getting the Speed number, I couldn't find Torque with a quick search. Either way, it's meaningless. In practice in the Speed you'll never actually achieve peak torque. There's no way to hold the engine down at the peak torque RPM when going WOT.
It doesn't matter if it's sand, dirt, pavement, etc. With the CVTs in SxSs ('cept the YXZ, of course) at high-load the engine is always in the peak HP range, not in the peak TQ range. Peak TQ is never realized in the actual vehicle, only on an engine dyno because it'll never be at WOT at peak TQ RPM in the completed vehicle.
What do you mean by "sucking up gas"? How does it depend on the HP/TQ curves? What does it matter if it takes X HP to move the vehicle through a given situation if it's making X HP at 5k or 8k? The shape of the curve really doesn't matter, ESPECIALLY with a CVT where you'll never traverse the whole power curve under high-load.
I missed your reply before... but I think you nailed it. It seems folks are conflating power density and "working hard." The latter of which isn't really a good metric for trying to compare engine platforms...
Ha... ya know.. both my cars have new motors so kinda still in 'break in'.. also.. I hate the belt changing.. so I'm no longer full 'hammer down'.. momentum is key with these CVT cars IMO... I was only full hammer down up a couple of hills when I raced the Orange vs. the Black... Seems like full hammer down as opposed to 2/3 throttle, .. doesn't really change it's performance.What do you mean by "sucking up gas"? How does it depend on the HP/TQ curves? What does it matter if it takes X HP to move the vehicle through a given situation if it's making X HP at 5k or 8k? The shape of the curve really doesn't matter, ESPECIALLY with a CVT where you'll never traverse the whole power curve under high-load.
Also, I'm assuming here we're talking about the same fuel in all cases. A given fuel (whether it's 91, 100, E85, whatever) carries a certain amount of energy by volume. So, it takes the same volume of fuel to create the same amount of power in any engine... BUT there's a HUGE and obvious caveat to that: efficiency. In internal combustion engines efficiency is generally measured by "Brake Specific Fuel Consumption" or BSFC.
The generic definition of BSFC is something like (stolen from a Summit page in this case): "BSFC stands for Brake Specific Fuel Consumption. It tells you how much fuel your engine will use per hour for each horsepower it makes. BSFC changes with engine load and rpm. A lower BSFC value is MORE efficient. Higher BSFC numbers are LESS efficient."
Now, here's where it gets good 'n complicated.
At WOT NA engines actually have lower (better) BSFC numbers. But it's not really apples to apples. A 999cc NA motor will have a lower BSFC than a 999cc turbo motor at WOT, but that's not what we're actually talking about. The question at hand is what are the BSFCs on a 225 HP NA 2.0L and a 225 HP NA 999cc motor. I don't think we have that data.
Further, since all of us other than @ANGRYBUTTCRACK don't dune wide-open 100% of the time we need to consider more than just full WOT. BSFC metrics change drastically in part-throttle conditions and there are opportunities to tune a turbo setup to beat NA BSFC for a given power output at part throttle. However, since none of these things are tuned for peak efficiency, more for power/longevity and to hopefully last when being beaten in the desert I doubt the turbo setup will ever realize the potentially better BSFC.
So, I'll agree for the same dune ride, I'd expect the turbo engine to use a bit more fuel. If the use of fuel is your definition of "working harder" I guess the turbo setup is "working harder." But others will define "working harder" by time at WOT or average throttle position, where the NA motor would be higher and therefore have been "working harder." Still others yet will define "working harder" by average RPM where I'd say the NA motor would clearly by much higher in a standard trans vehicle, but in an CVT setup both will hang out around peak HP RPM (though the NA motor probably has a higher peak HP RPM). So, by that definition of "working harder" it's a wash, or yet again the NA motor is "working harder."
Me, I would define working hard as the amount of work done, and on identical weight machines on the exact same route, on the exact same wheels/tires etc. if their speed were identical I'd argue neither worked harder, because both did the same amount of work...
Allllllllllllllllllllll of that said, I think the point here is that "working harder" isn't a real metric that can be properly quantified or measured and arguing about it is pointless... which is why I do it.
-TJ
Why you got to go all technical on us lay people. LOL!!!What do you mean by "sucking up gas"? How does it depend on the HP/TQ curves? What does it matter if it takes X HP to move the vehicle through a given situation if it's making X HP at 5k or 8k? The shape of the curve really doesn't matter, ESPECIALLY with a CVT where you'll never traverse the whole power curve under high-load.
Also, I'm assuming here we're talking about the same fuel in all cases. A given fuel (whether it's 91, 100, E85, whatever) carries a certain amount of energy by volume. So, it takes the same volume of fuel to create the same amount of power in any engine... BUT there's a HUGE and obvious caveat to that: efficiency. In internal combustion engines efficiency is generally measured by "Brake Specific Fuel Consumption" or BSFC.
The generic definition of BSFC is something like (stolen from a Summit page in this case): "BSFC stands for Brake Specific Fuel Consumption. It tells you how much fuel your engine will use per hour for each horsepower it makes. BSFC changes with engine load and rpm. A lower BSFC value is MORE efficient. Higher BSFC numbers are LESS efficient."
Now, here's where it gets good 'n complicated.
At WOT NA engines actually have lower (better) BSFC numbers. But it's not really apples to apples. A 999cc NA motor will have a lower BSFC than a 999cc turbo motor at WOT, but that's not what we're actually talking about. The question at hand is what are the BSFCs on a 225 HP NA 2.0L and a 225 HP NA 999cc motor. I don't think we have that data.
Further, since all of us other than @ANGRYBUTTCRACK don't dune wide-open 100% of the time we need to consider more than just full WOT. BSFC metrics change drastically in part-throttle conditions and there are opportunities to tune a turbo setup to beat NA BSFC for a given power output at part throttle. However, since none of these things are tuned for peak efficiency, more for power/longevity and to hopefully last when being beaten in the desert I doubt the turbo setup will ever realize the potentially better BSFC.
So, I'll agree for the same dune ride, I'd expect the turbo engine to use a bit more fuel. If the use of fuel is your definition of "working harder" I guess the turbo setup is "working harder." But others will define "working harder" by time at WOT or average throttle position, where the NA motor would be higher and therefore have been "working harder." Still others yet will define "working harder" by average RPM where I'd say the NA motor would clearly by much higher in a standard trans vehicle, but in an CVT setup both will hang out around peak HP RPM (though the NA motor probably has a higher peak HP RPM). So, by that definition of "working harder" it's a wash, or yet again the NA motor is "working harder."
Me, I would define working hard as the amount of work done, and on identical weight machines on the exact same route, on the exact same wheels/tires etc. if their speed were identical I'd argue neither worked harder, because both did the same amount of work...
Allllllllllllllllllllll of that said, I think the point here is that "working harder" isn't a real metric that can be properly quantified or measured and arguing about it is pointless... which is why I do it.
-TJ
