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RX400h

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Posts posted by RX400h

  1. Our 94 Nissan had 152 HP out of a V6, so I'd say its compression was very low as well. Yet, it pinged hysterically at 110+ degrees F. I'm sure the lexus wouldn't actually ping long enough for the driver to hear it, but the end result would be a reduction of horsepower. I'll bet if you were to test it on a dyno, the difference would be easily seen.

  2. With ambient temps like that, I'd make sure to use nothing but premium gas. Otherwise, your RX will be down 50 HP. It was 92 degrees here, yesterday, but I've experienced first-hand the 110+ temps in Vegas. That's why I'm staying as close to the ocean as I can!

    Wow, premium makes that much of a difference?

    Of course, I was inflating the number, but I do know that higher intake air temps can easily cause my Corvette's ECU to !Removed! timing enough to reduce RWHP by 10.

    Many years ago, My family and I were in Las Vegas in August, driving our Nissan Quest van. It was pinging so badly on regular gas (never a problem in San Diego) that it felt like power was cut in half.

    General rule of thumb: If your engine is going to ingest >100F air, use premium fuel.

  3. Someone asked the editors at Car & Driver that very question and the editor replied that this is why they have long-term testing - to let the readers know what they may be in for if they purchase that particular vehicle. Of course, manufacturers like Mercedes love the initial impressions, because many consumers (who don't subscribe to CR) see only those and not the long term versions.

    Even CR will rank a known-unreliable vehicle at the top of a list if that vehicle performed well, but CR will NOT place a "recommended" check mark next to it, telling readers that they should stay away.

  4. From the latest Road & Track magazine:

    All environmental ruminations aside, Lexus has engineered one heck of a car that has blazed an entirely different path for hybrid cars. The V-6 GS 450h was never meant for stellar 40-plus-mpg city/highway cruising and yet its performance-

    focused nature doesn't negate the fact that it has averaged better fuel economy (25.2 mpg) than 73 percent of the cars we've long-term tested in the last five years, 20 percent of those cars equipped with 4-cylinder engines. Rising gas prices have played a role as our previously tested Audi A3 2.0 T burned the same amount of fossil fuel during its 50K stint as did our GS 450h, yet the GS 450h's gas bill was $148 more.

    Adhering to the Lexus-recommended 5K maintenance schedule meant relatively frequent visits to the dealer usually at a minimum of $144 per visit, but nothing out of the ordinary in cost compared to other luxury marques. In fact, our Lexus undercut our recently tested Chrysler SRT8's routine maintenance by $498 and our Cadillac CTS-V by a whopping $2272, largely because we needed to replace the Lexus' run-flat Bridgestone Potenza RE040s only once.

    If you've been following this test, you already know that we've had only a single issue with the car, a bad O2 sensor (covered under warranty at 15K miles). To not hear a creak or a squeak since then from any area of a first-generation vehicle is an amazing feat. And with as many electronically controlled features as this car came with, not a single function went awry.

    Seated in the GS while making final notes on wear areas, I was in disbelief that the interior had actually seen 50,000 miles of action. The leather interior, even in its cream hue, showed almost no signs of fatigue save for a couple of spots on the driver-seat's left bolster. All the charcoal-colored wood trim from the dash to the armrests is in excellent condition and free of delamination. Even the console buttons and window controls look as if they've not been used by passengers. In fact, the only real blemished pieces I could find were the light gray floormats, which would set you back about $110 for a new factory set of four.

    Should we have the power to change anything on future generations of GS 450hs, a unanimous decision (and one we've almost beaten to death) would be the placement or size of the battery. This is the one really big limiting factor in long-distance travel as the trunk is barely large enough for two medium luggage cases. This converts this comfortable 5-seater city car into a 3-seater GT if your passengers come with any luggage.

    An item up for debate is the drop-drawer on the dash that provides a home for 14 additional control buttons (trunk and fuel-door releases, mirror adjustment, etc.), which some found cumbersome to access or painful if left open and bumped into. Personally, I found the panel a good solution as you would have to otherwise find 14 individual locations for the buttons within the cabin.

    Last but not least, as enthusiasts, we're never too pleased to have our freedom policed by the invisible reins of stability control. In this case it was Lexus' aggressive VDIM (Vehicle Dynamics Integrated Management) that, especially with such a potent hybrid powerplant at our disposal, led us to believe that the GS 450h's sporting potential was never fully realized.

    We know you are changing your direction, Lexus, the new IS F being proof of this, and we like where you are headed!

  5. Our 2006 never pulled to either side, but the tires did not wear evenly and the dealership mounted, balanced, and aligned our replacement tires, the Bridgestone Alenzas, free of charge. We've now put on at least 14,000 miles on the Alenzas and they are wearing very evenly. Certainly, they will last far longer than did the OEM Goodyears.

    One thing to note is that the door jamb sticker is incorrect in that it lists 30 psi as the correct tire pressure. I've found that 35-36 psi is ideal.

  6. The upcoming Corvette ZR1 will crank out a minimum of 620 HP and will rank among the very fastest cars in the world at ANY price! (It will cost approx. $100,000) By the way, I have read that Porsche has the highest profit margin of almost every automaker. The performance they deliver just doesn't match up with the cost, IMO, but that's a whole "nuther" discussion.

    I'm happy to see that those MIT guys at A123 are seeing successful results. Many of us can benefit from all-electric commuter vehicles.

    Dave

  7. I don't know about buttons on the 08, but if the 08's are like the prior 06-07's ... yes, you can disable 'em. However, it's not recommended, it can void the warranty, and cause damage to boot, it you over rev while disconected

    If there is, in fact, a button (installed at the factory) that can do this, then it's a bit hard for me to believe that the warranty can be voided. My Corvette gives me the option of turning off just traction control (competive driving) or both traction control and active handling. I never turn off active handling, as it is not intrusive at all and can really save my car and me from wiping out at times. However, turning off traction control allows proper launching of the the car if at a dragstrip.

  8. Holy moly, talk about hitting a raw nerve! :(

    I just finished reading an editorial in Design News magazine about the conspiricy theory (that still circulates parties) of GM's collaboration with the oil companies to kill the electric car and the 150 MPG carburator. Although I am not well-versed as to the whole story of the demise of the GM electric car, I do know that there was nothing in the same league as my Corvette when I bought it. No, it has not been the most reliable car I have ever owned, but for the money, its well-rounded performance couldn't be touched by anything else.

    Dave

  9. Massachusetts startup develops new battery for electric cars.

    Technology Review (May/June 2008, Bullis) reported that A123 Systems, "a startup in Watertown, Mass.," that is working on lithium-ion battery technology, has "attracted the interest of General Motors (GM)." GM is testing A123's batteries "as a way to power the Volt, an electric car with a gasoline generator; the vehicle is expected to go into mass production as early as 2010." According to Technology Review, A123's batteries "store more than twice as much energy as nickel-metal hydride batteries, the type used in today's hybrid cars, while delivering the bursts of power necessary for high performance." In lieu of cobalt oxide, the batteries "use an electrode material made from nanoparticles of lithium iron phosphate modified with trace metals." As a result, they are less likely "to catch fire, even if crushed in an accident," and are "much hardier than conventional lithium-ion batteries." Technology Review noted that the "A123 batteries for GM's Volt store enough energy for 40 miles of driving, enough to cover daily commutes," while a "small gasoline engine" would be used to "recharge the battery" on longer trips.

    In other news.....

    Toyota Prius sales reach one million mark.

    The AP (5/15, Kageyama) reported that Toyota's Prius, which "started out a decade ago as a risky experiment in green technology," is now "the world's first mass-produced gas-electric hybrid vehicle to hit the one million mark in sales." The Prius "is now sold in 40 countries and regions," while "its popularity is going strong amid surging gas prices and growing" environmental concerns. Toyota Motor Corp. "sells other hybrid models, but the Prius has been by far the most popular model." The automaker "has said it plans to sell a million hybrids annually sometime in the few years after 2010."

  10. The "Driving conditions" factor cannot be overstated. Being that the majority of us live in fairly large cities (or close to them), payback comes at a much faster rate than calculated by the various "experts". For example, the MPG advantage attained if heavy traffic is encountered every workday can mean a difference of 80-100% between a non-hybrid and hybrid. City mileage for non-hybrid SUVs is often atrotious, to say the least.

    Even at 4-5 years payback, most owners of hybrids will enjoy the benefits many years beyond that, as the average length of vehicle ownership in the US is approaching 10 years. (Canada's is just a bit over 8 years).

    Based upon the durability and reliability of our RX400h, there really is no reason to buy a new vehicle anytime soon.

    As far as stocks are concerned, this is not a good time to day-trade unless you really know what you're doing.

    Regarding resale value: Hybrid SUVs are holding their value far better than their non-hybrid counterparts.

  11. Fuel prices, competition among hybrids reduce buyers' payback period.

    In the front page of its Money section, USA Today (5/12, 1B, Carty) reports, "Rising fuel prices and competition among a proliferation of gasoline-electric hybrids have sliced the payback period for hybrids to two or three years in some cases, instead of five years or more that made hybrids harder to justify at lower fuel prices." Moreover, "increasing interest in hybrids is driving their prices up and eroding their fuel cost-saving benefits." According to an analysis by auto-price consultant Edmunds.com, "the difference between a Toyota Camry hybrid and a similarly equipped gasoline Camry was $889 Friday, up from $850 a week ago. Assuming 15,000 miles a year, Edmunds figures just 1.7 years for the Camry hybrid's fuel savings to offset the car's higher price -- slightly longer than 1.6 years when the price difference was less a week earlier." USA Today notes, "Besides Camry hybrid and Toyota Prius, there are hybrid versions of Honda Civic, Nissan Altima and Chevrolet Malibu, among others, and an array of SUVs. If gasoline goes up just a few cents, payback time falls dramatically."

  12. WWest, I'm sure you heard of the new Tesla all-electric sportscar. Here's what a Lithium battery expert has to say about it:

    "I used to work for a Li-ion battery company and have reviewed the technical aspects of the Telsa. There are a number of articles out there but they fail to mention a few items.

    1. Safety. The Telsa uses 6,831 Li-ion battery cells normally used in laptop PC, cordless power tools, etc. Each cell is a little larger than a AA cell. At 100% charge, this is over 50,000 watts. Thats a lot of electric energy!!! The Prius only has about 1,300 watts. You may recall all the articles about the recalls on lap top batteries. These are exactly the same type. While these batteries have the most energy density, they are formulated based on Lithium Cobalt, which has a very low flash point. Which means, if there is an internal short in one cell due to damage (accident) or manufacturing defect, all the cells configured in parallel will dump there energy thru the damaged cell resulting in tremendous heat and fire. The heat and fire is so intense, the surrounding cell will catch on fire setting off a chain reaction. The car will burn down, the garage, the house or building. Telsa advertises they have liquid cooling and other safety measures, but it won't help if the car is in an accident or if a single cell has a manufacturing defect.

    2. Weight. The battery pack and all the related electronics weigh about 900 lbs. Yikes!

    3. Battery Life. The average life of a Li-ion battery is 400-500 cycles. This is based on the standard industry rating of 80% depth of discharge. The market price for a Li-ion cobalt cells is about $2.50 so to replace a complete pack, you probably talking over $25,000-$30,000 once you factor in the packaging.

    4. Long charge cycle. You would have to charge this overnight with such a large pack and the charger would be huge (expensive). Assuming a recharge to 100% from 80% discharge (about 40,000 watts), a 120 volt charger at 20 amps (2400 watts), charge efficiency of 80%, it would take 20 hours to recharge. Using a 240 volt charger at 20 amps, that would cut the recharge time to 10 hours. In Tesla's favor is a commuter would only need to recharge once a week. But long trips would require stops every 200 miles +- and recharge.

    5. Green. Li-ion cobalt cells contain heavy metal and while they can be recycled, its tough.

    While electric vehicle performance is something to behold, batteries technology is the key. Li-Ion cobalt cells widely used in laptop PC's is definitely a "no-no" on safety alone. There are manufacturers of safer Li-Ion Phosphate cells (Valence Technology and A123), but their energy density is 40% lower currently requiring more cells for the same energy capacity. But they are safer plus have a 2,000 cycle life. But they still are based on small cells of which any could fail making replacement very difficult. Once larger cells are commercialize (10x - 20x), then it will be a simple matter to pull and replace any failed cell."

  13. It's very tough to have better filtration AND higher flow. I've used K&N filters for over 20 years and in every case, hydrocarbon concentration in each of the cars, steadily increased. If you want all-out performance and accumulate low miles every year, I don't blame anyone for going with a hi-flow filter. However, if you want your vehicle to last 200,000 miles and you do pile on the miles, stick with the OEM filter.

    How can you tell if your filter is letting in more dirt? Get an oil analysis while you have the stock filter in-place and do the same after a time while running the high-flow filter. If the dirt level is higher after the same number of miles, you'll know what the likely culprit is.

    Okay, first of all, and I think all would agree, the only advantage for any "free-flow" intake air filter occurs ONLY at WOT and fairly high engine RPM, LOADED engine RPM. Otherwise the throttle plate itself is the major obstruction to HIGH VOLUME intake airflow.

    So.

    If a free-flow intake air filter is so desireable why hasn't someone designed an intake bypass that opens an intake path around the filter with WOT...??

    You would then have the advantages, long engine life, of the OEM filter but still have that extra 5-10 HP (whatever, at least the THRILL of the intake noise/sounds) with WOT.

    I rather doubt that street use of any vehicle would allow enough WOT, filter bypass, to compromise the engine life.

    ...probably, liability reasons is my guess. many folks install electric exhaust cutouts to bypass their mufflers, but this really doesn't harm the engine. In fact, some new cars come with a similar type of bypass that is activated by throttle position.

  14. It's very tough to have better filtration AND higher flow. I've used K&N filters for over 20 years and in every case, hydrocarbon concentration in each of the cars, steadily increased. If you want all-out performance and accumulate low miles every year, I don't blame anyone for going with a hi-flow filter. However, if you want your vehicle to last 200,000 miles and you do pile on the miles, stick with the OEM filter.

    How can you tell if your filter is letting in more dirt? Get an oil analysis while you have the stock filter in-place and do the same after a time while running the high-flow filter. If the dirt level is higher after the same number of miles, you'll know what the likely culprit is.

  15. For the most part, the more city mileage you drive, the better the average fuel economy. So yes, this sounds like the perfect vehicle for you. Does the iphone have GPS navigation? I highly recommend the navigation option in the RX. I compared it directly to a Garmin NUVI 660 and I felt that the Lexus Navi has the edge when it comes to voice-guidance. Yes, the 660 is less expensive, but the Lexus Navi is very convenient to use.

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