Why do some auto makers limit to 155mph? | FerrariChat

Why do some auto makers limit to 155mph?

Discussion in 'General Automotive Discussion' started by zippyslug31, Oct 19, 2009.

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  1. zippyslug31

    zippyslug31 Formula 3

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    What is the significance of 155 mph and why don't others (Ferrari, Lambo, etc) have this same limitation?
    It's not like a, for instance, 5-series BMW can't do faster than 155 yet they are limited.
    155 mph appears to be a very particular (and obtuse) number.

    Is it simply due to the rating of the OEM tires?
     
  2. JMOrem

    JMOrem Formula Junior

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    #2 JMOrem, Oct 19, 2009
    Last edited: Oct 19, 2009
    This is from 2005 but still true as far as I know. I think its akind to Japanese car companies "limiting" the advertised HP of their cars to something like 276. As far as how they arrived at 155MPH I haven't a clue.

    http://www.autoblog.com/2005/07/14/manufacturers-may-lift-155-mph-limits/

    "It started out years ago as a 'gentlemen's agreement'. Now, the 155-mph speed limit found on Audi, BMW, Lexus, and Mercedes cars may be lifted after years of being a fact of life. Started as a means to prevent government regulation, this self-regulation is not followed by all manufacturers out side of these four. With more and more manufacturers producing cars that are significantly faster, these four are talking about lifting the limit on their regular production vehicles. The limit removal is being looked into by Audi, BMW, and Lexus. Lexus was not one of the original manufacturers when the limits first were imposed."

    More here as well:
    http://www.thetruthaboutcars.com/by-thy-speed-limits-thy-shall-be-known/

    German Speed Limits: I Can’t Drive 155
    By Robert Farago
    December 30, 2006



    There I was, flying down a German autobahn in a VW Phaeton, bumping up against the car’s electronic limiter. I glanced at the rear view mirror and moved over. A modified M5 streaked by at over 180mph. I say modified because BMW is part of a “gentleman’s agreement” hammered out in the 70’s, when Germany’s Green Party wanted to impose speed limits on de-restricted autobahns. Mercedes, BMW and Audi all agreed to limit their products’ top speed to 155mph. The idea that other countries could build automobiles capable of cresting 250kph somehow escaped everyone’s attention. As, eventually, did the entire speed limit issue.

    At the time of the agreement, the majority of the automobiles plying Germany’s highways weren’t particularly clean or mind-numbingly fast. Some thirty years later, the tailpipe emissions produced by Germany’s increasingly modern automotive fleet are virtually sterile. And there’s hardly a new vehicle sold that can’t comfortably cruise well over 100mph— from diesel delivery vans to four-cylinder passenger cars. And so they do. At the same time, BMW, Mercedes and Audi all build mainstream models that could easily exceed their 155mph e-limit. And so they do, once a friendly tuner remaps their ECU. (FYI: Porsche never joined Club 155.) Clearly, German gentlemen kick ass.

    Today’s German greens are also in butt kicking mode. Now that cars no longer belch significant amounts of harmful pollutants into the atmosphere, environmentalists are taking a new angle of attack: carbon dioxide. They claim that automotive CO2 emissions help reduce the Earth’s natural cooling, which causes global warming. This concern has resurrected the Green Party’s attack on automobiles in the same way that studies on the harmful effects of second hand smoke on non-smokers reignited the anti-smoking movement. Throughout the European Union (EU), member states are busy imposing legislative measures designed to restrict vehicular CO2.

    The greens also have a new champion: Andreas Troge. The President of Germany’s Federal Environmental Agency (UBA) is a long time auto industry critic. For example, at a 2004 conference on environmental sustainability, Troge lambasted carmakers for using technological innovation to increase engine performance, rather than reduce fuel consumption. Last Thursday, Troge called for a 75mph speed limit on all German autobahns. He declared that the move would reduce Germany’s carbon dioxide emissions by 30 percent.

    The speed limit proposal is best seen within a much wider and more vigorous debate. The EU is currently trying to “convince” Germany to radically reduce its CO2 emissions. Specifically, the EU wants the German federal government to impose tougher CO2 restrictions on its power providers. Germany’s four largest utilities have rebelled, warning that any such concession will reduce energy supplies, eliminate jobs and increase prices– which are already the highest in Europe. Whether the autobahn speed limit will be a successful part of a growing environmental movement or nothing more than a doomed sideshow remains to be seen.

    I’d bet on the sideshow. No less a personage than Germany Transport Minister immediately dismissed the 75mph speed limit [almost] out of hand. “I am committed to a reduction in emissions,” Wolfgang Tiefensee proclaimed. “But a general speed limit on open stretches of road does not make sense.” Tiefensee and his supporters assert that autobahns are environmentally irrelevant; they account for just two percent of German roadways. Defenders of the status quo also maintain that derestricted autobahns help the national automobile industry develop better and safer automobiles.

    While the exact correlation between allowing 100mph+ driving on long straight roads and increased automotive safety may be a bit unclear, the underlying sentiment is not. Even without considering the merits of the safety argument, the fact that such a counter-intuitive justification can be mentioned in public without widespread condemnation highlights the enormous cultural importance of Germany’s derestricted autobahns. In other words, planet, schmanet. Don’t EU be messing with our autobahns.

    Remember: Germans are a people who won’t jaywalk– even if there isn’t a car anywhere within sight. They can’t run their washing machines or wash their car on a Sunday– in case the noise disturbs their neighbors. In the main, they like rules. But they also like their autobahns. And that's because the roads liberate them from stifling peer pressure and governmental dictat, giving them a rare chance to explore and experience their individuality. Not to put too fine a point on it, German drivers revel in the sheer joy of accelerative release. The derestricted autobahn network is a precious bastion against soulless conformity.

    That will one day fall victim to political conformity. While environmentalism is not likely to slow down German drivers, safety legislation will. The European Union is about to harmonize drivers’ license requirements across national boundaries. It’s only a matter of time before Brussels standardizes Union-wide road safety regulations. Reigning-in Germany’s derestricted autobahns may be the last step in this process, but it will also be one of the most significant. And regrettable.
     
  3. Fred2

    Fred2 F1 World Champ
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    For one, 250 Kph = 155 mph.
    It is my understanding that German bumpers are crash tested at 250 kph. Due to the TUV, they are not allowed to travel faster than the crash test rating the are approved for.
     
  4. JMOrem

    JMOrem Formula Junior

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    #4 JMOrem, Oct 19, 2009
    Last edited: Oct 19, 2009
    Crash rated to 155? There isn't a bumper out there that'd survive that...

    I'd love to see the video from the test.
     
  5. ZiFF

    ZiFF Formula Junior

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    Bumpers aren't going to do a thing hitting an object at 250 kph. Whether you have the biggest bumpers ever put on a production car to date, or no bumpers at all, would make no difference at that speed.
     
  6. TheBigEasy

    TheBigEasy F1 World Champ
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    IMO - It won't be long before the USA mandates all "road legal" vehicles are limited to 100mph or less...
     
  7. Bas

    Bas Four Time F1 World Champ

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    German gentlemans agreement. They could have unlimited speeds on the autobahn BUT all german manufactures had to limit their car to 155. Porsche didn't honour it though, and lately BMW has been cheating significantly (in the M6 for example...7th gear, 155mph, shift down to 6th, keep the power on and you'll see 200 eventually in 7th:D).

    Not sure why it was though.

    Japan had an agreement too, not to exceed 276 bhp. Nissan had been cheating with the R33 and R34 GTR, the R33 produced around 290-300 while the R34 could hit almost 330bhp. They wrote 276 on the paper though, lol. Shortly afterwards it was scrapped
     
  8. Kaivball

    Kaivball Three Time F1 World Champ
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    LOL.

    No.

    Kai
     
  9. wax

    wax Five Time F1 World Champ
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    The speed limit is to keep Valets from doing even more damage to the drivetrain.
     
  10. kosmo

    kosmo Formula 3

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    the 155 is not a Legal limit. In fact I've seen some AMG's offered w/ a option to remove the limit, at extra cost, of course.
     
  11. NeuroBeaker

    NeuroBeaker Advising Moderator
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    That was my understanding as well. The industry decided to govern themselves to some extent (allowing small loop-holes) before the German government decided that average drivers were going too fast on the Autobahn roads and imposed a maximum legal speed. Hence, the 250kph/155mph gentleman's agreement between the German manufacturers.

    All the best,
    Andrew.
     
  12. zippyslug31

    zippyslug31 Formula 3

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    No kidding?
    What is that limit?
     
  13. Bas

    Bas Four Time F1 World Champ

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    Not in Germany, unless the dealer is slightly bending the rules. Rest of Europe do get the option:).
     
  14. NeuroBeaker

    NeuroBeaker Advising Moderator
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    Sorry, I wasn't clear... the German manufacturer's gentleman's agreement was put in place to pre-empt the German government getting it into their head that they needed to impose a limit. As yet, there is no limit - at least in the dry.

    When it's raining or foggy, there is a limit but I'm not sure what it is. Still pretty high speed though.

    All the best,
    Andrew.
     
  15. mwr4440

    mwr4440 Five Time F1 World Champ
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    My bet:

    They (Bavaria at least) will loophole the "No Speed Limit" Autobahns just like Amsterdam loopholed and gets away with keeping the "Tea Houses" open.


    Lots of Will-- Lots of Ways.
     
  16. UmarS2K

    UmarS2K Rookie

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    Hahah
     
  17. darth550

    darth550 Six Time F1 World Champ
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    That has always been my understanding.....
     
  18. ztunelover

    ztunelover Formula Junior

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    Ok heres why I think they downrated the top end to 155mph, rather than going on.

    1: The Gentleman's agreement that everyone mentioned.
    2: I remember Clarkson modding a rover with a massive turbo, and then blowing it up. Somewhere around there he brought out an amg, and pointed out some ludacris horsepower output most modern amgs do put out, then said they only go to 155. Remember what he explained why they didnt put a limiter on? 200mph car needs suspension, aero, tires, brakes, on top of the powertrain to properly hit 200mph. 200mph pieces cost money, so to keep costs down and prices down they restrict the top end.

    I personally agree, high horsepower and torque numbers is not a difficult achievement these days, but making sure the rest of the car can handle the stress of 200mph can get pricey. Look at the m6, or even the m5. They are fairly pricey, they were built to put up with the pressure the car feels at 200mph, although I doubt they would be very stable at those speeds.

    Certain overengineered machines can (r34) but they also carry a fairly ridiculous pricetag. If you look at the big picture, power is easy, speed not so much. Sure acceleration can be improved, but that last extra bit of stress from air pressure can make a front splitter to rip. Want to see what happens when the front end loses downforce? Watch what happened to nakajima this brazilian gp.
     
  19. VIZSLA

    VIZSLA Four Time F1 World Champ
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    I know that BMW lowers the limit from 150 to 130 when the sport suspension and its larger tires aren't chosen.
     
  20. James_Woods

    James_Woods F1 World Champ

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    Yup, I was told it started as a German auto industry self-regulation in the hopes that it would avoid even more draconian measures from their government.

    Tires, also.
     
  21. jm2

    jm2 F1 World Champ
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    Believe it or not , many times it's tires . They have various speed ratings , and ride and handling characteristics play a role as well . Often times the cars can easily exceed 155 mph , but the tires aren't up to the task . So the manufact. puts a speed limit to govern top speed .
     
  22. konatown

    konatown F1 Rookie

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    Tires are the most modern safety concern with limiting speeds.

    Very few tires sold can deal with the stress and growth that occurs above 135MPH let along 155MPH.

    I strongly advise any of you that participate in a high speed run on your normal set of tires to have the condition checked immediately.
     
  23. ztunelover

    ztunelover Formula Junior

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    Exactly my point. stuff capable of taking 200mph worth of abuse is going to be more expensive to manufacture right?

    A Y rated tire would need a different construction method than a W rated tire, where a W rated tire would start delaminating after 270km/h a Y rated needs to hold up to 300km/h, some of them even more.

    That costs money, remeber most of those cars are mass produced machines, and unlike Ferrari owners most of their owners dont want to drop 10k like that on them. So even little differences in maintainence cost would start driving customers away.
     
  24. Bas

    Bas Four Time F1 World Champ

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    If they can't find a loophole...there's always france:D.
     
  25. menoy

    menoy F1 Rookie

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    #25 menoy, Oct 21, 2009
    Last edited: Oct 21, 2009
    Yo dawg!! :D




    PS Sorry, couldn't resist it... ;)



    As in? I heard France is quite strict on their speed limits...
     

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