AutoblogGreen

Rather humourous, but of course pointless. Why, you ask? Because a Prius buyer would never buy that BMW or vice versa. Toyota knows that Prius buyers will drive their car gingerly, so they have maximized the car for that. And what's wrong with that? Conversely, the M3 was designed for speed. If the buyer can afford to buy the car, then they will be able to pay for the gas, even if gas costs $15/litre. So fuel economy is not a priority. Different priorities. Completely different cars. Completely different buyers.

Still, it makes for a humourous watch. And if anything serious can be taken from it, it's that driving behaviour does indeed play a large part in fuel economy.

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No fair that BMW is drafting.

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Gotta love how they start out by repeating the same debunked-over-and-over-and-over myths about the environmental damage of building a Prius. Starting off with the old "nickel myth" (clue: Toyota only buys about 1% of the plant's output, and the overwhelming majority of the damage from the plant was done back in the 60s and 70s, before it was cleaned up)

Even at top speed, I doubt their claim on the Prius's mpg, too.

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In these particular circumstances, I'd imagine it's plausible that the Prius got worse mpg. (Hummer first supplied its cars wiht a smaller engine, but that engine was too slow. Then they made they replaced it with a larger engine. The larger engine got the same mpg as the smaller engine because they small one had to rev so much to keep speed)

I like Top Speed, but it makes me cringe how they stigmatize some alternative fuel cars. Do they realize the power they have?

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proves what happens when engine is working 100% compared to one just working like 20%

if you think about it the 4.4liter engine runnign at 20% is pretty much consuming as much fuel as a 800 CC engine working at 100%

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Still trying to contact Jeremy re:Henney for sale
Is it possible this little electric didn't sell.
Please respond......Richard

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M3: Base weight 3704#
Prius: Base weight 2932#

If you accelerate the same mass along the same velocity profile the acceleration takes the same amount of energy. The BMW might have somewhat better aerodynamics (higher cD, but much smaller frontal area), and the Prius might have lower rolling resistance (narrower, higher pressure tires) and might get a bit back from regen, not a lot though.

So can a big V8 produce more usable energy per gallon than a little I4? Its possible at just the right conditions, but I suspect if you looked at the velocity profiles of the two vehicles there were NOT actually identical. I'll bet the BMW carried a bit more speed through the turns.

But still the point is valid. If you drive in a race, you'll get shit mileage.

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The BMW should have driven next to the prius not behind, or they should have stayed way back to eliminate aero effects.

The H2 had the 5.3 & 4 SPEED AUTOMATIC, the H2 [upgrade] received the 6 speed automatic & variable camshaft timing.

The transmission efficiency of the BMW double clutch is impressive. 7th gear is 1:1 so you only have 1 gear mesh from engine to axle. (well if it is a stick car, the same pertains to 5th gear)
The prius transaxle is a mess. 2 gear meshes + 1 transfer chain, plus the power split device operating over the unity speed (electric overdrive)
http://www.techno-fandom.org/~hobbit/cars/training/800/ptrain.jpg
previous gen. prius
http://www.flickr.com/photos/31809458@N00/399978739/

The prius has a lower Cd and swept area than the M3

So the answer, negating the huge transmission disparities, is BSFC.

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i dont really see why you guys think this "test" is insulting the prius all Top Gear is saying is change the way you drive and you can save gas they just exaggerated this Top Gear Top Tip with this example

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Nonsense. The M3 is probably at 1500rpm and the Prius is working hard at 6000rpm. Prius is 1.3 litre, so it becomes equivalent to 1.3x4=4.2 litre. So, Top Gear is fxxking our minds. Like a comedy and I don't watch the show any more.

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He should have compared the Prius to a Corvette. That thing gets amazing highway fuel economy for a fast sports car, rated at 26 mpg on the highway (versus 20 mpg for the M3). The GM OHV V8 is designed efficiently to just loaf along at highway speeds and the car is very aerodynamic. If the Vette could be fitted with narrower, lower rolling resistance tires, that could be an efficient (fast) highway commuter car.

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he hates the corvette because its an American car that out performs any British pos. Opps did i say British? I meant Chinese,Indian, Arabian, Russian,German owned British name

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The main advantage of a hybrid is its regenerative braking which powers electric-assisted acceleration. The electric motor on the Prius isn't even active above a certain speed.

They way they drove them was in no way similar to the EPA mileage tests. Not surprisingly, the way they drove them was in no way similar to how 99.9% of the people drive on the streets. So this test isn't even applicable to most of us.

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I've long suspected the poor mileage of the prius (relative to high mileage cars of the 1980s) is all the extra weight and complicated gubbins they carry around. Once you get above a certain speed and the electric motor stops, then all that stuff becomes a hindrance.

Granted for stop-start driving in big cities, hybrids make sense, but for a highway commuter, if you stripped out the batteries and electric motor from a prius, and just had it as a very lightweight gas-only car, it would be a lot more efficient.

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Obviously Virgil has NO CLUE as to how a Prius works.

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People are missing the point of the test. Jeremy even said at the end that an M3 is not a more economical choice than a Prius, just that driving style has a lot to do with what king of MPG you get. Even if you drive a Honda Civic, you will get bad MPG of you floor it from stop light to stop light.

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This is the same Clarkson who drove from London to Edinburgh and back again on a single tank of diesel (~40mpg) in an Audi V8 TDI in Top Gear series four, episode four. The point is *how* you drive makes a huge difference in economy.

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This is the same Clarkson who drove from London to Edinburgh and back again on a single tank of diesel in an Audi V8 TDI on Series Four, Episode Four. The point is *how* you drive makes a huge difference in economy.

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The folks at Top Gear must have nothing to do. this test was pointless. A direct comparison between a Prius driven economically and driven hard would have made some sense. They just wanted to play and get paid for it.

Karkus, since the Prius yields better mpg in stop and go city driving than it does on the highway, where is virgil wrong? The losses between the engine and the electric motor would not be present if the Prius were driven directly by an ICE. I would expect the mpg figures to reverse and the vehicle would be more efficient on the highway and less so in the city. Small frontal area, lower Cd, low rolling resistance tires etc. are ploys that have been used effectively before.

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BTW, why do they make the audience stand (at attention)? Love the show but Jeremy is clearly up himself.

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