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  • brightness04brightness04 Member Posts: 3,148
    The answer is quite simple:

    0-60/62 (100km/h) is a poor yardstick for measuring vehicle performance in general, and an especially poor one when comparing cars with different drive train types. An extra gear shift makes all the difference.

    Also, MB automatics/engine combo are apparently quite poor in keeping the gassers in the power band for doing 0-60/62 test. Official MB numbers don't involve clutch dumping.
  • lexusguylexusguy Member Posts: 6,419
    0-60/62 (100km/h) is a poor yardstick for measuring vehicle performance in general, and an especially poor one when comparing cars with different drive train types.

    Perhaps, but there is no wider used metric for comparing one car to another than 0-60. According to M-B, the E320CDI should be compared to the E350, and not the E280. Also, how many E-class owners drop their clutches (or even order the manual at all)? You can complain all you want about M-B's choice of ratios, but the fact is the E320CDI will win.
  • tagmantagman Member Posts: 8,441
    An extra gear shift makes all the difference.

    It sure made the difference for the '07 LS460, with it's 8-speed automatic, that was deliberated low-geared in 1st and 2nd to make up for the lack of low end torque, which, BTW, is what diesels have inherently by design.

    And to say that 0-60 has no meaning... well, it sounds like you'll say anything to argue, because, as lexusguy points out, that measurement is one of the most widely used measurements on the planet. Yikes.

    TagMan
  • tagmantagman Member Posts: 8,441
    IMHO, clean and smooth-running diesels that delivery massive power output is a bit like the joke about fuel cell cars in the industry: heralded for decades but never materialized as a feasible production model.

    I'm glad you made that remark as your opinion, because if you represented it as a fact, you would be wrong. We are VERY close to seeing even more clean, smoother diesels with terrific power output available for all 50 states, with some of the cleanest emissions when compared to the majority of modern cars.

    We will see them earliest from Mercedes, Chrysler side as well, Audi, BMW, VW, Nissan, Honda, and eventually Toyota and the others.

    TagMan
  • designmandesignman Member Posts: 2,129
    0-60/62 (100km/h) is a poor yardstick for measuring vehicle performance in general, and an especially poor one when comparing cars with different drive train types. An extra gear shift makes all the difference.

    Maybe you mean 0-60 alone? In any event you should elaborate on that comment. Empirical observation of acceleration is the bottom line. The more split times the better. Furthermore, it's the only way right now to compare performance of ICEs to hybrids in addition to poring over wheel dynos which aren't readily available.

    I wish all car brochures and websites would provide engine and wheel dynos but they're useless with hybrids.
  • brightness04brightness04 Member Posts: 3,148
    E320D is comparable to E350 in price, but in terms of engine displacement and performance it should be compared to E280 . . . as both engines are 3 liter (and E280 actually delivers nearly 10% more power than E320D), whereas the E350 has a 3.5 liter engine. While E class driver don't drop dump their clutches often, they don't clock 0-60 races often either. As soon as the E320D needs to take the next shift, the numbers are reversed.
  • brightness04brightness04 Member Posts: 3,148
    If a car's gears are designed for 0-60/62, it will take an extra 3/4 - 1 second to do 0-65 . . . some of it due to that extra 3mph speed but most of it due to a need to shift in to a higher gear. Cars with high torque but low hp can do good 0-60 because they need to shift less below 60mph, but falls rapidly behind as soon as additional shifts are needed at higher speed, where horsepower is the ultimate arbitrator on performance. Car nuts went through that debate a decade ago with Mustangs' switch from 5L to 4.6L . . . the same thing happened two decades ago in the debate between Porsche 911's vs. Chevy Corvette. Ultimately, people caught on and realized horsepower is what really matters unless all one care about is 0-30 sprints to the other side of the intersection . . . in that case, hybrids with big electric motors would have a huge advantage.
  • brightness04brightness04 Member Posts: 3,148
    In case it's not obvious, when I said "an extra gear shift makes all the difference" in the context of 0-60, an extra gear shift is actually a huge _disadvantage_ . . . because it takes time. A car with torquy low-revving engine can get through 0-60 with less gear shifts than a high revving engine. As a 911 owner, you should know first hand that a high horsepower but relatively low torque car is not designed for running 5-60 or 0-60 without clutch dumping starts. However in terms of real performance, a car like 911 can very much live up to what its horsepower rating implies despite a significant torque deficit compared to cars like Corvette and SVT Lightening.
  • brightness04brightness04 Member Posts: 3,148
    That was my point. We have been promised "VERY close" for over half a decade. The reality is that they can't even make a 208hp one 50-state legal. 208hp is significantly less than even typical V6 family sedans nowadays.
  • lexusguylexusguy Member Posts: 6,419
    The displacement of the E350 doesn't matter. The 3.0L BMW 535i is going to crush it on the street. How is that possible? Shouldn't the 535i be compared to the E280 because they are both 3.0L engines? It's not an apples to apples comparison, just as the E280 v E320CDI aren't the same. Diesels don't make horsepower, they make torque, which the CDI has boatloads of. The E320CDI has far more torque than the E350, let alone the E280. If you go by torque rather than the horsepower you seem stuck on, then it should be compared to the E63.
  • designmandesignman Member Posts: 2,129
    I agree with everything you said but you're into tangential details and getting a little off the point. One thing has to be taken into consideration: Horsepower is the ultimate arbiter at high speed, however torque rules at lower speeds. Somewhere in between there must be a balance for the street which is a medium where high-horsepower/low-torque F1 cars are useless. My point is that acceleration times are the bottom-line metric in comparing straight-line performance. That's all. It is debatable what is optimal for the street. If you want sport, add revs. If you want to overtake on highway entrances get low-end torque.
  • tagmantagman Member Posts: 8,441
    That was my point. We have been promised "VERY close" for over half a decade. The reality is that they can't even make a 208hp one 50-state legal. 208hp is significantly less than even typical V6 family sedans nowadays.

    Sure, sure... whatever you say. Put the blinders on tight and just don't look when the first 50-state clean diesels are here in only a few more months, cause I guess you won't believe your eyes.

    TagMan
  • blkhemiblkhemi Member Posts: 1,717
    A quick diesel lesson for you brightness:

    First off, diesels are not at all big on horsepower. They make their power from deep within, and that is called torque.

    Secondly, yes 208hp is quite low in light of todays V-6 engines, where at least 300hp is the bare minimum.

    BUT, diesels are in a different ballpark. 208hp is actually quite good for the relatively compact 3.0L engine. Consider that a 6.6L Duramax TD Silverado puts out 360 horses. Yes that's over 150hp more, but it also comes with an engine that's roughly double the size of the MB.

    Look at the Bluetec this way also:

    Did you know that the small 3.0L MB TD not only makes more torque than the E550, but also the mighty BMW M5? Yes it is true it is more than a second slower to 60 than the E550, two more than the M5, but neither can return the E320's 30-32 mpg range. In fact, nothing in the luxury class in the USA touches that.

    MB deserves at least that much credit, and I'm here to give it to them.
  • blkhemiblkhemi Member Posts: 1,717
    Recently, my wife and I were testing most of the luxury utes on the market today.

    First up, the Range Rover Supercharged- Very refined, almost Lexus quiet cabin. The performance is nice, altho the non-supercharged 400hp Escalade will smoke it. Some controls are haphazardly placed(in true English fashion, even my XKR has this issue), but the choice of materials and workmanship is top notch, probably at the top of the class with LX chasing a close 2nd. And yes the $90k is hard to justify for an SUV(especially coming from a $45k Jeep Commander LTD), but one drive proved otherwise, much easier to swallow than the Porsche Turbo S' $112k. And to top it off, the Jaguar/RR owner let me have his personal RR to have for 3 days to assure me that it was well worth it. It also helps that I just dropped $90k to him on an XKR earlier this year, but who's counting... And Tag, I see why you like it

    The Escalade- Very high cool/bling factor. Chromed from head-to-toe, this is the vehicle that you need if you need to be seen. Add in the 22" chromed wheels, and you're in like flynn on the next season of MTV cribs. IT's hard to ignore it's prodigious power: 403hp 6.2L V8 mated to a lightning quick shifting 6-speed autobox(in a GM?) and gets to 60 in 6.0 secs flat. But it's the details in the interior that threw me off: A non-telescoping steering wheel and one that tilts manually, a not-so-useful 3rd seat and still has to be removed to get a flat load floor are just a couple of the big blunders that left me scratching my head in this $69k big ute.

    The SRX: Many of you know that this has been one of my favs for a long while, but the updated interior makes even more the merrier. She really likes this one.

    Tomorrow: MB GL450. She kicked the ML off of the list yesterday after having spent the day with one of her girlfriend who drives an ML500. She said the interior is very cheap(something I've heard numerous times) and that MB "lost it's edge on the ML". The ML has never been one of my favs, and this generation probably won't change that, even the ML63 power-rocket as the SRT-8 JGC still smokes it and the Turbo S Porsche.

    We've drove the Q7 for a week when I had the Audi's in for service. This vehicle is still at the top of the heap.
  • jlbljlbl Member Posts: 1,333
    A turbo diesel engine may have both, and at lower revs.

    May I add that an Audi R10 with a V12 2T Diesel Audi 5499 cm3 engine was the absolute winner at the last 24 Hours du Mans edition? (Average speed : 215,409 km/h)
    http://www.lemans.org/24heuresdumans/live/pages/retro/historique_gb.html

    And that the new Peugeot 908 HDi FAP has won the 1000 km Monza race of the Le Mans Series, 13-14-15 April 2007?
    http://www.lemans.org/24heuresdumans/live/actu/2007-04-16_GD_1297_fr.html
    http://www.lemans-series.com/2007/uk/monza/resultats.asp
    http://www.lemans-series.com/2007/uk/index.asp

    Race and street cars with diesel engines are here to win. Sure in tight competition with good gassers (and others?) :)

    Regards,
    Jose
  • houdini1houdini1 Member Posts: 8,356
    Jose, thanks for the info. You are one of the few people on this board who has had extensive experience with a diesel as an every day driver. Please share your opinion as to how diesels stack up against gas engines in day to day service.

    Here is the big question. If initial cost and operating costs were the same, which would you choose, gas or diesel?

    2013 LX 570 2016 LS 460

  • drfilldrfill Member Posts: 2,484
    That was one of the first things I noticed when the "Slade came out was it had no telescope, no power wheel, much less auto tilt-away! That's just straight ghetto! :P

    And with the 3rd-row, those two can kill a lot of deals.

    The Range has a great interior, but the exterior is aging quickly.

    DrFill
  • brightness04brightness04 Member Posts: 3,148
    the 535i be compared to the E280 because they are both 3.0L engines?

    Not until E280 delivers 300hp.

    Diesels don't make horsepower, they make torque, which the CDI has boatloads of.

    Diesels do make horsepower, just less of it, and horsepower is what gets delivered to the wheels. Wheel torque, not engine torque, is what matters. Maximum wheel torque is limited by the horsepower avialable (minus air friction x velocity) divided by wheel rpm. Power = torque x rpm; powre = force x velocity. Focusing on torque or force alone is quite meaningless when power number is available.

    If you go by torque rather than the horsepower you seem stuck on, then it should be compared to the E63.

    So by that logic, if I hook a 10-to-1 reduction gear onto a Honda Civic engine (which itself produces 128 ft-lb) and threby getting 1280 ft-lb at the new axel sticking out of the new black box, can it be proclaimed the new monster engine just because its torque doubles that of an E63? Of course not, because the total power output is still only 140hp! The torque is increased to 1280 ft-lb, sure, but rpm is reduced to 630rpm instead of 6300rpm. Horsepower already reflects torque times rpm.

    Back when cars were gear-limited, with 3 forward gears or something, having a high torque number had the advantage of being able to stay in power band for a peaky-curved engine. Nowadays, 5,7 and 8-gear transmissions are becoming common place, staying in power band becomes a lot easier. 0-60/62 numbers often reflect a quirk associated exactly with 0-60/62; shifting once to 60/62 vs. shifting twice to 60/62 becomes a huge factor when each shift itself costs double-digitl per centage of the time involved to 60/62. A one-shift 0-60/62 car (ie. one that is able to reach 60/62 in second gear) may well fall behind another one that takes two shifts to 60/62(ie. reaching 60/62 in third gear) by the time the speed is beyond the reach of the second gear!
  • brightness04brightness04 Member Posts: 3,148
    Torque is important for low speed when the transmission only has a small number of forward gears. In order to get reasonable fuel economy at high speed for gasoline engine (in which too lean fuel mix would lead to detonation that would destroy the engine, unlike diesels where detonation is the mode of operation so leaning out fuel mix at cruise speed would be fine), the top gear has to be high enough to result in reasonably low rpm at high cruise speed. With that end fixed down, if the transmission only has a small number of gears like in the days of 3-speed automatics, there simply wasn't enough gears down below to bring the gasoline engine into the power band at low vehicle speed.

    Nowadays, transmissions offer much more gears. F1 cars can actually do very well for acceleration on smooth streets. It's the low ground clearance that may get them caught in pot holes. That has nothing to do with engine characteristics.

    The engine torque itself doesn't get trasmitted to wheels per se (difference in reduction gearing throws that torque number way out of wack; that's why the final gear ratio is often a decisive factor in tuning old cars for 0-60, often at the expense of other performance numbers). Power is what gets transmitted through the drive train. Torque band does have influence for specific low speed tests such as 0-60 when transmission gearing is limiting avaiable rpm (hence power available). When comparing cars with drasticly different torque-rpm curves, 0-60 only reflects 0-60 and little of anything else because the next shift at 65mph could well turn everything upside down because the high torque car may have achieved better 0-60 through less gear shift through 60/62.
  • brightness04brightness04 Member Posts: 3,148
    A quick physics lesson for you blkhemi:

    Power = Torque x rpm

    Engine torque is not the same thing as wheel torque. Trasmission reduction gears are what connects the two. Different cars can have entirely different transmission gear ratios. Your own example that 320D having more torque than M5 but three seconds slower doing 0-60 shows t hat torque matters not much in performance. Why? Because power is what ultimately decides performance. Power is what gets put down to the wheels. If I enclosed a 10-to-1 reduction gear in Honda Civic's 140hp/128lb-ft engine, the output of the new black box would be 140hp/1280lb-ft but with peak horsepower at 630rpm instead of 6300rpm. Would that suddenly make you swoon over Honda Civic? Hopefully not.
  • brightness04brightness04 Member Posts: 3,148
    Le Mans is an endurance race. The diesel cars won by having to stop for fueling less often. What's more, neither of the two engines mentioned could pass emission test in all 50 states.

    Hybrids (heavy flywheels powered by electric motors) in contrast won race track speed races so spectacularly that they were subsequently banned from racing for "unfair" advantage.
  • designmandesignman Member Posts: 2,129
    It's nice to talk about the characteristics of torque, horsepower, gearing, speed, acceleration, all of the components of automotive dynamics. But what's your point beyond carrying on a didactic, contentious discourse?

    The formula for F1 dynamics is useless for the street so don't even go there. And don't try to lessen the importance of torque. There is no horsepower without torque and the ideal situation for speed is to have as much torque as possible at as much RPM as possible. But going to extremes with both is hardly possible so it's all in the balance and tradeoffs depending on what characteristics the manufacturer wants to achieve for their markets.

    BTW, I'm all for electric because of its very desirable properties. We know what the problems are there.
  • blkhemiblkhemi Member Posts: 1,717
    I merely used the M5 as an example of how much torque a diesel engine generates over a comparable gas model.

    The E320 CDI accelerates 0-60 in 6.7 seconds, all the while returning 30-35 mpg. In contrast, the E350 gets there in 6 seconds flat and returns a 23 mpg overall. Sure there will be miles that would be need to be driven to recoup the cost of $1k, but in light of the $3.16 I paid today to fill up, it won't take long.

    Factor in that the CDI is one of the quietest TD's ever made(never been a prob for MB) and it's relatively low cost of maintenance(for now until Bluetec gets here, and even then it is said to miniscule due to the long intervals for urea) and it's a no brainer.

    Again, I have to applaud MB's effort on this. No need for batteries and electrical hype. These diesels do just fine.

    BTW: I love your presentation of how the power gets put down. But without turbo's, just about every passenger car's diesel would perform horribly, yes, all the way up to the big rigs. It's nice to get that power down to the ground, but first you must spool that power from the engine to do so.
  • blkhemiblkhemi Member Posts: 1,717
    If Caddy had spent the money on a power tilt/tele steering wheel w/memory and exit functions and also on a power-fold or tumble third seat versus spending the budget on tons of chrome, they'd have been considered a bit more as the powertrain is rock-solid
  • brightness04brightness04 Member Posts: 3,148
    My point is actually quite simple: horsepower ratings already encapsulates torque numbers, as in horsepower = torque x rpm. If we are to talk about ideals, reduction gears should be available to bring whatever rpm the engine needs to deliver peak power down to the wheel rpm at a given speed. 7 and 8 speed trannies, besides obvioiusly CVT, have come to quite approximate that ideal.

    Sure more torque and more horsepower is nice, but when one has to choose one over the other, horsepower trounces torque almost every time. Even the M1A1 tank uses a relatively low-torque but very high rpm hence high horsepower engine; talk about an application where one would think high torque would be nice as it's essentially a super heavy truck, from a transportational point of view. Yet, a nice reduction gear can turn that low torque at high rpm to exhorbitantly high torque at low rpm. Just like I mentioned earlier about attaching a 10:1 reduction gear to the 128lb-ft little four banger from Honda to produce 1280 lb-ft at the output end. Horsepower is what stays constant (minus some small frictional loss). Torque is easily transformed by reduction gear ratios.
  • brightness04brightness04 Member Posts: 3,148
    208hp is already with turbo. Without turbo-charging, my guess is that a 3.0 non-turbo diesel would probably deliver 100hp or less, due to low rpm.

    The difference between 23mpg vs. 32mpg is 147 gallons over a 12k mile year (522 vs. 375 gallons). Even at $3.16/gal, that's $465/yr. The price difference between 228hp (C280) vs. 268hp (C350) is over $5000 at C class price level; at E class price level, the gap would probably be greater . . . and the E320D generates 20hp less than even C280. If 40hp is worth $5000, 20hp additional difference(with even greater per centage due to smaller base number) would be worth an additional $2500. That's $7500 difference at C class price level. E class cars are about 30% more expensive . . . even if we assume the price gap due to power output stayed the same unaffected by that 30% base increase, that would mean buyers of E320D are paying an estimated $8500 price premium over a gasoline E class that developed 208hp peak power. How long will $465/yr gas savings add up to $8500 in a 6%-interest environment? Just about forever plus a few years because $8500 principal would generate an interest payment of $510/yr.

    BTW, "quietest TD" doesn't mean much when it has to compete against cars that are not plagued by the noise of diesels to begin with.
  • brightness04brightness04 Member Posts: 3,148
    I have been waiting for clean diesels that deliver high power for well over a decade . . . it's always a few more months to a model year or two away . . . then followed by a few low-volume productio samples that misses one or both of the qualifiers.

    The "new" turbo diesels coming online face a couple additional problems:

    (1) The old I-5 diesels and turbo diesels from MB back in the 80's were designed and built ground-up as diesel engines. Even MB gasoline engines of that era were based on diesel designs; hence MB engines of that era were greatly over-engineered . . . a big part behind their reliability reputation back then. Nowadays, as I check through the block specs, it looks like the V6 diesels are derived from gasoline engine designs. Whether that's due to cost/material savings or weight saving purpose, I do not know. I do know what happened when GM built diesel engines based on existing gasoline engine designs back in the 80's.

    (2) Oil change schedule is critical to diesel engine survival, both due to the high compression ratio and the mandatory turbo (in order to deliver anything more than 100hp or so). With today's luxury car buyers getting used to change oil every 10,000 miles, the diesel maintenance schedule will stick out like a sore thumb. Those who skimp on oil change, either due to being cheap or due to lack of time, will see their diesel engines die.
  • tagmantagman Member Posts: 8,441
    D-Man's reply to brightness =

    what's your point beyond carrying on a didactic, contentious discourse?

    :D

    D-Man, if you haven't copyrighted that, may I borrow it once in a while? ;)

    TagMan
  • jlbljlbl Member Posts: 1,333
    "Le Mans is an endurance race."

    24 Hours du Mans (de Le Mans) is an endurance race. A race of the Le Mans Series is an intermediate 621.37 miles race. (Because of that I posted information on both races.) Next F1 race in Barcelona is a 190.82 miles speed race.

    There are no diesels in F1, though it may be 1-3 tank refills per car and race, it depending on the circuit and the team strategy. True, F1 cars are all for hp, with up to 19500 rpm or more. Their engines are prepared for a maximum of two races with their classification sessions. The driver must manage to keep the engine at as high revs as possible at any moment. I am sure you know well all this.

    I do not see all that is necessarily good for a street car or a luxury car. As Designman has posted, it must be a compromise between hp and torque (resulting in an appropriate performance/driving comfort balance). Diesels have evolved a lot nowadays. They are clean and can be cleaner. (Here, we are environmentalists, too.) When turbocharged, they offer a reasonable compromise between hp and torque. For that reason I think they are winning ground so quickly in Europe. Of course, apart from the price of fuel. Yet fuel price has resulted in giving a choice of engines to the drivers, and then we have found that diesels are not only suitable for saving money but also for having fun driving.

    ".... today's luxury car buyers getting used to change oil every 10,000 miles, the diesel maintenance schedule will stick out like a sore thumb."

    Let me say that my 2004 BMW 530d (L6cyl, 3L, 218hp, 368 lb•ft from 2000 to 4000 revs, max speed, autolimited,152.24m•h) is scheduled to change oil every 12427 miles (20000 km). Indeed, it is not necessary to change sparks.

    Sorry, this has resulted a long post. It is not intended to angrily confront any other. As Houdini1 asked me, I try to give my experience as every day driver of a modern diesel.

    Regards,
    Jose
  • jlbljlbl Member Posts: 1,333
    Houdini1, you have asked me a very good question. So good that I have mumbled the answer for some hours. Here it is.

    My BMW 530d (manual, 6 speed) is ideal for long road trips and every day commuting. The engine is so agile in delivering good speed and acceleration that I do not envy any LPS at the road. I get fun in driving it, both on highways and mountain winding roads. It takes corners with precision and comes out of them with so much power that traction and stability control is a must for your peace of mind (and security). The position of the pedals is good for the heel-and-toe maneuver. Overtaking other cars and trucks can be done confidently on double-way roads. The turbo delay when stepping down the acceleration pedal is not perceived. Even for downtown driving my big diesel is not bad at all, if I were able to find parking sites along my path. Oh! Yes, my diesel is still a little bit noisier and more vibrator than gassers. It does not smell more.

    However, there are times I go for the other car in the family, a 115 hp 2004 Mini Cooper gasser. That occurs when I need to hear the nice noise of a gasser engine at high revs. Or to feel the instant and elastic power elicited by the acceleration pedal in a gasser engine—again, next to its rev upper limit. Or the joy of having to test my ability in changing gears to keep that feeling as the road goes on and the corners come quickly up. But this costs money and it is not for everyday use ;)

    I have to say that my actual BMW 530d is my first diesel. All my life I drove gassers (I am 57 year-old, if that matters). I have been very reluctant to drive diesels. In brief, their lacking of hp was aggravated by their noise, smell, vibration and pollution. (I know well, my daddy had a 1960something MB diesel bought in Germany——Spain was not very wealthy at the time). I am not a professional driver, nor I am related in anyway to the car/engine business. But I like driving. I feel I would have liked to be a good rally driver :P :blush:

    In conclusion, gassers are fun to drive, but modern diesels may give you a somewhat more relaxed fun driving. For dayly driving I would choose diesel at present time.

    Regards,
    Jose
  • cdnpinheadcdnpinhead Member Posts: 5,621
    ". . . . modern diesels may give you a somewhat more relaxed fun driving. . . ."

    Very nicely put, Jose, and I agree wholeheartedly. I've driven several diesels in Europe and was initially amazed at how quiet & free of exhaust smell they were/are. Now I just want one over here, preferably in a entry-level lux vehicle (BMW, Audi).

    The thing about diesels is the low-end torque. Having 2XX hp available at 9000 rpm (see S2000) is interesting, but more wearing (on the driver as well as the drivetrain) than having it available at 4000 rpm, in my (never) humble opinion. In a roadster, having to keep the engine above 4-5K to be able to accelerate at all may be tons of fun, in a lux sedan. . .not so much.
    '08 Acura TSX, '17 Subaru Forester
  • blkhemiblkhemi Member Posts: 1,717
    Brightness, you can't be serious enough to compare a E320 CDI to a C280, right? And yes the CDI makes less horseppower and is heavier, but why does it smack it silly in performance in fuel and acceleration?

    You claim to be a numbers guy, but you missed the mark completely on this one. The only way to figure real "difference" is to compare the E320 CDI to a model within it's own line, and that is the E350. The C-Class' dynamics differ all together, even tho it has the 3.5L V-6 optional.

    BTW: Those cars that you say aren't plagued with noises aren't diesels in anyway, and many of which are louder than the E320 CDI at full throttle, including some Lexus models.
  • blkhemiblkhemi Member Posts: 1,717
    Agreed. :)
  • houdini1houdini1 Member Posts: 8,356
    Thank you my friend for a very thorough and well considered answer. It probably took you a while because, in retrospect, my question wasn't really fair.

    Obviously, there is a fuel cost saving with the diesel and with your fuel prices/taxes this has to be a major consideration. Hopefully, very soon, we will also have the choice of a good, clean diesel here in the U.S.

    2013 LX 570 2016 LS 460

  • bristol2bristol2 Member Posts: 736
    Agree also.

    Brightness- I also don't understand your insistence that HP is more important than torque simply because torque is used in the calculation of HP.

    Distance and gallons-used are used in the calculation of mpg but neither distance nor gallons-used are less 'valuable' than mpg. BTW, diesles get better mpg, that's why people are interested in them. It has nothing to do with HP, torque, noise, soot or any of the other factors. It's mpg.
  • brightness04brightness04 Member Posts: 3,148
    it must be a compromise between hp and torque (resulting in an appropriate performance/driving comfort balance).

    That is true when transmission flexibility is limited, like in the days of 3-speed automatics. Think of it this way, if all cars were CVT's that encompassing a very wide range of ratios, do we really think Torque would even be a relevant specification? I don't think so. An engine that produces 250hp peak at 5454rpm would be exactly the same as 250hp peak at 2727rpm after fitting a 2-to-1 reduction gear . . . even if the torque of the former is exactly half of the later. With 7 and 8 speed automatics available from major carmakers, that kind of transmission flexiblity is becoming reality.
  • brightness04brightness04 Member Posts: 3,148
    yes the CDI makes less horseppower and is heavier, but why does it smack it silly in performance in fuel and acceleration?

    1. There is no such thing as "performance in fuel." The bulk of diesel fuel saving comes from ruising and idle. Diesel engines can reduce fuel consumption by leaning out fuel mix without having to worry about detonation because compression combustion (detonation) is how diesel engines work.

    2. I already addressed the issue on acclearation. 0-60/62 is a very quirky measure that breaks down when comparing cars with drasticly different hp/torque relationships. With 0-60/62 typically achieved within 7 seconds range nowadays, the result is heavily influenced by the gear shift count necessary to get to 60/62mph. For a relatively low torque but high horsepower car like E280 or Porsche 911 (when the latter is compared to the likes of Corvette), 0-60/62 presents somewhat of a design delimma that is unique to 0-60/62 test: in order to get the engine into power band in low speed, the cars really should have 3 gears below 60/62mph. However, if designed that way, two gear shifts would bring a 1/2 to 1 second handicap in physically shifting gears compared to a car that can get to 60/62 in the first two gears (therefore only one shift necessary). If second gear is tall enough to reach 60/62 in a low torque but high hp car, then the engine is not in power band at low speed. As you can see, this condition is quite unique to 0-60/62 tests. Once the speed get to 65 or 70mph, the diesel would need to shift into 3rd gear too, then suddenly you will see 1 second slower number to only a few mph more, which seem quite absurd until you think of gear shifting points. Alternatively, if a high hp but low torque car is designed to get to 0-60/62 in two gears, then the car is not optimized for 0-60/62 due to lack of gears to put the engine in power band at low speed, but chances are that it would then have phenomenal passing speed at 50-90 because now the engine is in power band.

    Those cars that you say aren't plagued with noises aren't diesels in anyway, and many of which are louder than the E320 CDI at full throttle, including some Lexus models.

    Like what? Besides, let's not forget the enormous hp difference brought on by the higher rpm.
  • brightness04brightness04 Member Posts: 3,148
    Brightness- I also don't understand your insistence that HP is more important than torque simply because torque is used in the calculation of HP.

    Okay, here's the logic: what gets put to the ground is not engine torque but wheel torque. The gear ratio between the engine and the wheels can be designed very differently for different cars. HP is what stays relatively constant (with only some minor frictional loss). Think of this way: if a 140hp/128lb-ft Honda Civic engine is wrapped up in a black box with a 10:1 reduction gear attached before the drive shaft comes out of the box . . . it's now delivering 1280lb-ft torque at the end of that drive shaft! However, the HP is still roughly 140hp because the rpm is 1/10 the original rate.
  • bristol2bristol2 Member Posts: 736
    Let me see if I can paraphrase this....torque is more based on gearing than engine 'speed'?

    If that's correct then surely with HP performance being derived from a calculation based on torque, surely HP suffers from the same effect?

    Pls rememebr I'm no engineer...
  • brightness04brightness04 Member Posts: 3,148
    HP = torque x rpm, but it's engine torque x engine rpm (for engine output) and wheel torque x wheel rpm (for dynometer treadmill test). The engine torque x wheel rpm (wheel rpm would imply vehicle speed) means absolutely nothing because we don't know what the reduction gear ratio is between engine and wheel.

    Engine torque is not directly applied to wheels because all IC engines, including diesels, have pathetic torque below low threholds like 500rpm, not even enough to keep itself running (i.e. the cause of engine stall); 500 rpm at the wheel would mean 35mph or so for a typical luxury sedan tire that rotates 800-900 revolutions per mile, no one can push start a car to that speed before starting the engine. So what happens is that the power delivered from the engine has to go through several reduction gears before getting to the ground.

    The reduction gears, while reducing rpm, obviously increase torque at the output end compared to the torque at the input end. Different cars can have very different reduction gears. That's why engine torque and wheel torque are not related by any constant factor. It can vary by a very wide margin. What does stay constant (more or less) in gear reduction is Power, with some parasitic loss.
  • brightness04brightness04 Member Posts: 3,148
    I can certainly agree with the example that you gave. However, for E280, peak power is around 6000rpm not 9000. For 10% more power than the diesel, revving from 4000rpm to 6000rpm may well be worth the effort, especially if all it takes is pressing down the gas pedal :-)

    I mean seriously, if people loved loud engines with good low end torque but run out of breath just over 4500rpm, they'd be buying old GM OHV pushrod engines. Even today's GM OHV engines are better than that.
  • jlbljlbl Member Posts: 1,333
    In my BMW 530d the range of useful revs is 1000-4000 (in a BMW 535d biturbo it starts from almost 0). 4500 revs is the max I can get in my car without getting into reds. So, I have 3000 revs to play with, the upper 2000 of these at full torque. I do not think that in any normal street/luxury gasser the useful range is wider than 4000 revs. I may be wrong, however. The difference would certainly be that in a gasser that useful range is made with more upper revs than in diesels.

    It is also important to notice that I get 76 mph with 2000 revs in 6th gear. In 5th gear, 2000 revs give me 64 mph and 3000 revs 94 mph, all of this with full 368.75 lb•ft torque. Similar good scales apply between speeds and torque at lower gears. This is very much forgiving when I want to drive quick but 'softly'.

    Regards,
    Jose
  • brightness04brightness04 Member Posts: 3,148
    I can certainly agree that turbo diesels make for very good cruising. In Europe, the luxury limo market used to be dominated by cars like 240SD/300SD/S280 etc., where high performance is not required nor desired, whereas low fuel cost to keep operating cost down is much appreciated by the livery service providers. There is just no need to compare 530d to 535i biturbo (gasser) or E320D to E350; they are very different animals.
  • tagmantagman Member Posts: 8,441
    There is just no need to compare 530d to 535i biturbo (gasser) or E320D to E350; they are very different animals.

    For God's sake, brightness, it's a natural and appropriate comparison. Write a letter to the editor of Car & Driver magazine and tell them that you disapprove of their recent comparison of the E-Class BlueTec to the E350. What were they thinking to actually feature such a comparison? And what were so many others thinking that wanted to know how well the BlueTec could stack up in comparison to the E350?

    BTW, that dirty diesel, as you've been calling diesels, just recently received the "World Green Car of the Year" Award at the NYIAS! Not so dirty afterall, is it?

    TagMan
  • heroletherolet Member Posts: 22
    According to C&D, the E-class Blue-Tec is actually about 1 second slower than gas-powered E350 from 0 to 60. The Blue-Tec has way more low-end torque but less HP. It makes people "FEEL" (yes, feel) faster, but the instructment results showes otherwise.

    "The bad news is that the E320 BlueTec is slower than the E350 in every respect. Our E320’s 0-to-60 time of 6.8 seconds trails the E350 Sport’s by 0.9 second, and the E320 is also slower than the 6.6 seconds claimed by Mercedes-Benz. The diesel might feel faster, but the numbers don’t lie." http://www.caranddriver.com/roadtests/12686/2007-mercedes-benz-e320-bluetec-verd- - ict-page2.html

    "When it comes to fuel-economy numbers, however, the diesel delivers. Our lead feet averaged 34 mpg on our trip, which included some city driving, and we were able to make the entire 650-mile journey on one tank. The E350 averaged 26 mpg,"

    The converter (or whatever they call it) is designed to last long if and ONLY IF the "super-clean" disel is being used; Otherwise, it will be damaged right away, and the cost to repair is about $2000. That so called "clean-diesel" is not widely available yet.

    We also should consider the following:

    Suppose we need 1-unit of petrol to produce 1 gallon of Gas,
    to make 1 gallon of Diesel, we will need approximately 1.25-unit (25% more).

    If 1 gallon of gasolin produce 1-unit of green-house gas, then 1 gallon of Diesel will produce 17% more green-house gas.
  • brightness04brightness04 Member Posts: 3,148
    People compare E550 to E350, too, but that doesn't make the two equal.

    BTW, that dirty diesel, as you've been calling diesels, just recently received the "World Green Car of the Year" Award at the NYIAS! Not so dirty afterall, is it?

    What exactly does "world green car" mean? Is it painted green or made of federal reserve notes? Mr. Inventor of Internet just received the Oscar less than six months after Newsweek retracted its article in 1975 that proclaimed that the governments of the world had to do something "now" in order to cope with the coming of global ice age. Those fanfares are nothing more than pinpointing turning points when looking back . . . like Nasdaq 5000 celebrations 7 years ago. . . wasn't 6000 supposed to be "anyday now"? We are still waiting 7 years later, just don't hold your breath :-)

    Also, notice the smaller front brakes and smaller wheels (16" vs. 17" standard on E350 and 18" on E350 sport) . . . the E320D is indeed equippped like an E280, which is not offered to the US market. The price premium for Bluetec Diesel is much more than the $1000 difference between it and the E350. We should add the $5000+ difference between E350 vs. E280 . . . that's for an engine that is not even legal in the most important luxury markets of California and Northeast. The upgrade next year to make it legal is probably not going to be free even if delivered as promised (which I doubt anyway).
  • brightness04brightness04 Member Posts: 3,148
    Herolet,

    Thanks for the link. I spent so much effort belaboring the point that even if E320D delivered better 0-60 than the gassers, it would fall behind shortly beyond 60mph . . . it didn't quite occur to me that MB actually fudged the numbers even for the first 60mph! hahaha! Almost a full second behind E350! and rapidly falling even farther behind on the way to 100mph, it's indeed an "280" class engine (even if that), not comparable to "350" gasser at all.
  • bristol2bristol2 Member Posts: 736
    Suppose we need 1-unit of petrol to produce 1 gallon of Gas,
    to make 1 gallon of Diesel, we will need approximately 1.25-unit (25% more).

    If 1 gallon of gasolin produce 1-unit of green-house gas, then 1 gallon of Diesel will produce 17% more green-house gas.


    This is nonsense. A barrel of oil makes a certain percentage of gasoline, diesel oil and other oils. It doesn't require more of a barrel to make diesel than to make gasoline.

    That so called "clean-diesel" is not widely available yet.

    Again, nonsense. ULSD is the federally mandated standard since October of last year.
  • blkhemiblkhemi Member Posts: 1,717
    Brightness, if you will, forgive my typo as I should've put the "E320 spanks it handidly in fuel econ and acceleration performance." Is that more understandable?

    The E320 is not at all that much about scooting 0-60. It does in a respectable 6.6 seconds, what more can you ask for something that returns 35 mpg in the process?

    And yes, the E320 CDI is in fact quieter than the GS300 at full swing. Even quieter than the old 5.0L MB 3-valve V8.

    Being "0.9" seconds to 60 versus the E350 is something I'd happily trade for. And given the many MB tuners that pull more power out of the CDI, it's a no-brainer.

    And let's remember, the E320 CDI has no direct rival in the States. Sure there is the 530d, A6 4.2 TDI, and Jaguar S-Type 3.0L TD, but they're not here. And only the Audi can directly compete as it uses some MB's own technology.

    "Like what? Besides, let's not forget the enormous hp difference brought on by the higher rpm."

    That doesn't make any sense whatsoever. That being the case, how does the MB S550 make the same 380hp the LS460 does? And this time, please reframe from using your transmision "gear tricks", as the heavier MB outpaces it all the while being short one gear. The LS460 is a screamer, yet the S550 does it in traditional MB(and for that matter, big engine) style, quiet and lithe. The 5.5L V8 allows MB to make this engine much more relaxed than the Lexus 4.6L by virtue of sure size.

    And I'll say it before you do, yes the LS460 does get better mileage, but we'll see how that pans out next year with the EPA updates as real world figures have been unimpressive for the LS460L, somewhere in the 17's, right thur with the Benz.
  • cdnpinheadcdnpinhead Member Posts: 5,621
    "Again, nonsense. ULSD is the federally mandated standard since October of last year."

    But it's so much more fun to have these discussions unencumbered by actual facts.

    Spoilsport! ;)
    '08 Acura TSX, '17 Subaru Forester
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