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2008 Toyota Highlander Hybrid - images courtesy Toyota Motor Company
Toyota revamps its Highlander Hybrid, carries over the powertrain

Toyota continues its push for hybrid vehicles with the new 2008 Highlander Hybrid. The new Highlander Hybrid and is based on the new Toyota Camry/Avalon chassis and rides on a wheelbase that is 3" longer. The vehicle is also 3" wider and 4" longer than the previous Highlander Hybrid.

Sadly, the powertrain for the 2008 Highlander Hybrid is a carryover from the previous model. In this case, the old 3.3 liter V6 (which itself is an outgrowth of the even older 3.0 liter corporate V6) and continuously variable transmission (CVT) is still being used to carry the majority of the load on the vehicle. There was speculation that the new 3.5 liter V6 would also be paired with the Synergy hybrid system used on the 2008 Highlander hybrid, but keeping the price down on the model was probably the reasoning for the carryover.

That being said, the Highlander retains its EPA rating of 31MPG/27MPG city/highway despite picking up an additional 500 pounds of heft. The 2008 Highlander Hybrid also offers the option to shut off the gasoline engine completely and run solely on battery power according to AutoblogGreen. The only problem is that the Highlander Hybrid’s NiMH batteries mean that you’ll only be able to travel an astonishing one mile on battery power alone.

GM’s 2009 Saturn Vue Green Line promises to deliver as much as 10 miles of battery-only power thanks to its lithium-ion batteries.

Pricing has not yet been announced for the new 2008 Highlander Hybrid, but expect modest price increases over the 2007 model. The 2007 model retails between $32,490 for a FWD Highlander Hybrid Base to $36,550 for an AWD Highlander Hybrid Limited.

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RE: ignorance
By DocDraken on 2/8/2007 6:35:30 PM , Rating: 2
Whatever you want to call it, the fact remains that a V8 with the same amount of power as a turbocharged 4-cylinder will use more fuel.

As for your misguided attempts at explaining torque, it's obvious you don't know a lot about turbocharged engines, as their typical characteristic is lots of torque low down. Your response reflects a common misconception.

There are several examples of turbo charged 4-cylinder engines dating back as far as the early nineties (225HP and 252 ft.lbs. already at 1800 RPM and plateau up to 4000 RPM.) Or how about 260 HP and 258 ft.-lbs. @ 1900-4500 RPM.

So your notions about "far less torque" from a turbocharged 4-cylinder is pretty dated.

RE: ignorance
By exdeath on 2/9/2007 12:09:39 PM , Rating: 2
Couple things I feel I should jump on here.

You can make any engine as powerful as you want. It doesn't matter how many cylinders. It all comes down to money. In the end, using the same leading edge materials, etc, a I4 is half of a V8 and will always be half as capable, a V twin will be half as capable as a I4, etc.

Case in point, look at the pro level nitro methane drag cars. Blown 8L V8 = 4000 HP. Blown 4L I4 = 2000 HP. Blown nitro methane v-twin drag bike = 1000 HP. Half the cylinders, half the power, half the size, etc. The limit is in the materials, and at this level of performance, you have the same materials in both engines allowing for the maximum power per cubic inch of air at the highest PSI possible.

The idea that a V8 has more friction is bogus. Its not like those added pistons are along for the free ride, they bring their own power with them to make up the difference. What you mean is that putting a V8 in a car that could get by with a turbo I4 is a waste of the V8's true potential over the I4 and simply lazy engineering. It's also marketing.

For people that don't think a I4 can make torque, look at this:

Thats 375 ft/lbs of torque at 3575 RPM from a 2.0L.

Torque is about airflow management throughout the RPM range. Maximizing air mass flow for peak horsepower will rob any engine of low end torque: Take a look at the high revving Ferrari V8s, lots of horsepower, and way less peak torque.

More displacement is always going make more power, just like more boost, more of anything that can flow more air. But there is also a limit to how large your cylinder bore can be before you lose precise control over ignition and flame front expansion, control that is critical to maximizing the power extracted from the mixture. It takes balancing of many many factors.

If you can turbo a I4 to run like a V8 with I4 mpgs, you can also turbo a V8 to run like a V16 with V8 mpgs. All that really matters is how much air you are pumping through the engine. When you reach the limits of boost, you can add more cylinders. When you reach the limits of how big your cylinders can be, you stuff more air into them with boost.

In the end its all the same goal: Burn as much air and fuel as you can without destroying the engine. With the best materials on Earth, you should realize that every engine configuration known to man would eventually lead you to reach a constant value. This value is a result of the maximum air/fuel density, maximum pressure, maximum heat, and ultimately a maximum power per cubic inch possible given the materials and the fuel used.

So once again, V8 = 2x I4, all else held equal. Of course you will see highly engineered I4s making the same or more power than under engineered V8s, most likely because someone got lazy or simply decided it was more cost effective to throw in a simpler V8 at half its potential to get the same power as a highly engineered I4.

As for reliability, that is also bogus. Forced induction does not increase the peak heat or cylinder pressure. What you get is a more constant plateau of pressure throughout the entire power stroke instead of a peak and a sharp drop off, but its still well under the peak. You get continued constant expansion throughout the entire power stroke instead of the top, particularly toward the bottom when the rod and crank are at 90 degrees and the work advantage is highest.

Yes this generates more heat, because you are getting more power. Basic physics, and this applies to any engine. IF you have a 2.0 I4 making the same power as a 4.0 V8, that I4 factory radiator isn't enough anymore, its going to need the same radiator capacity as that V8. Again, basic physics.

As for hybrids... the engine in a hybrid has nothing to do with the MPG. The car design itself is more to do with it. You can't stick a Prius engine in a Camry and get 60 mpg. The design of the car itself as a system has far more importance than the engine. The Camry would have to be shaped like a Prius, made out of plastic, carbon, and aluminum, and not have power this power that power everything robbing power from the engine via hydraulic pumps, etc.

RE: ignorance
By exdeath on 2/9/2007 12:16:51 PM , Rating: 2
Oops, that graph shows 375 ft/lbs at 3500 RPM.

Whats a LS1 put out, 300-400 ft/lbs at 4500 RPM?

This isn't a X engine is better than Y engine comparison, just a simple illustration. You could turbo the LS1 and build it with the same materials and make twice the power as the I4.

But the point is, they DONT. They use an engine with too much potential for their power goals without using that potential, and as a result, you pay the price associated with a bigger engine.

Its the same reason gas turbines are not used in cars. They are way more efficient than piston engines, but only at sustained power levels far more than what is needed for a car. To nerf it down for a car would get crappy mpg and all that draw backs of that type of engine with none of the advantages.

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