Down Tuning/Power Restricting. Exploitation or Useful Too?

Discussion in 'Gran Turismo 5' started by Stigsblkcousin, Jul 12, 2011.

  1. Stigsblkcousin

    Stigsblkcousin

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    Some say that using the power limiter to down tune a car from 600pp to 475pp, for example, to meet restrictions is somewhat cheating. Apparently, when you down tune a car, the acceleration and torque characteristics remain the same as it would be if it were not down tuned.

    From what I've experienced, it does seem to be some truth to that. A tuned LFA restricted to 500pp will demolish a RX-7 fully tuned and unrestricted 90% of the time.

    What are you guy's thoughts on this and do you think there needs to be an option to run cars at the "True" pp/hp only?
     
  2. Tornado

    Tornado

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    It really depends on the car more than anything else.



    That being said, there should be an option set by the host to limit how much the limiter is set.
     
  3. GTlondoner

    GTlondoner

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    By the graph you get max power through more rpm so there must be an advantage.
     
  4. Starking

    Starking

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    The quickest fix would be make it so the game doesn't give you the flat power-curve. Instead you get you're original power-curve no matter the limiter.
     
  5. maxpontiac

    maxpontiac

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    I think it's fine as long as it's not a race car v. street car scenario.
     
  6. bass264

    bass264

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    This frequently happens online, I get in a street legal car and someone downtunes a GT500 car and gets 4 seconds ahead the person in second place.
     
  7. iamsupernasty

    iamsupernasty

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    If you were to take two otherwise identical cars:

    Leave the engine stock on one of the cars.

    On the second car do all the power mods to the engine. Then de-tune the motor back to the stock horsepower.

    In this game the second car will be faster. Always. With every car.

    The reason is because the power limit effectively gives the cars a completely flat HP & Torque curve.

    A normal car that's rated at 400 HP only has that much Horsepower for a very narrow section of the powerband. By using the power limited you can give that car 400HP for the entire powerband. While the maximum horsepower has not increased, the usable horsepower has increased dramatically.
     
  8. Morgoth_666

    Morgoth_666

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    They should add some sort of PP modifier to changes made with the power limiter to negate that effect, or allow room hosts to limit the amount of power limiting to, say 10% or so.

    But like everything else in GT it's always a rough compromise. A race car at the same PP as a road car will generally win as it doesn't fully take handling into account, same with all the bits you can put on the car that don't have an effect on PP. Of course it's impossible to simulate the performance gain of a car that suits its driver either.

    It's nice that it's a little easier now to get a room-full of people to all find a way to make one of their cars fit the regulations, maybe a future patch will make some improvements to how it's calculated.
     
  9. watermelon punch

    watermelon punch

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    This is why I constantly try to bring this to the attention of people new to the game, and new to online racing. Because if you don't know it, then you will be at a disadvantage.

    And I think that's rather stupid.
    IE: If you like winning races because you know some "secret" flaw in the game but your opponent does not know it - in reality, you have not won them on a level playing field. Taking advantage of someone's ignorance of the flaws in the game is nothing special nor does it prove anything, nor is it any type of fair competition.

    That said, in the organized races I host, I make sure that everyone knows this is what is going on.
    That there's no way to restrict against it and police it, so everyone needs to do it. Because the host can't stop people from doing it... and among any group, there could always be one person who would be tempted to use it to cheat if they thought they could get away with it. :rolleyes:
    This way, you CAN have a fair race, as long as everyone is informed, and has the knowledge & opportunity to tune for the best torque/power under whatever restrictions are set for the race.

    OTOH, I really wish there were game provided controls that allow you to restrict use of the power limiter, ban the power limiter, and even ban various upgraded parts. I don't know why this isn't an option, because it would make it a lot easier to have more fun & fair online racing!!

    While it is true that it depends on the car as to what combination of upgrades & power limiter, and at what PP or hp/weight, the car will do best.
    But all things being equal, using the power limiter to meet a restriction is pretty much always better on all cars than upgrading just to the restriction.
    I doubt that there's even one car in the game that would perform better without use of the power limiter than one that is using the power limiter, at the same hp/weight.
     
    Last edited: Jul 13, 2011
  10. Krazie Ivan

    Krazie Ivan

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    from my experiences and testing, not every heavily restricted car will beat one w/o restrictions every time.

    each car is different, which means each BHP/Tq graph is different and changing certain parts or using the Power Limiter affects BOTH halves ...but not equally... as BHP peaks and stays flat throughout the powerband, while Tq peaks early and drops off hard. and then there's track dynamics - some place importance on grunting out of low-speed corners for long bursts of accel uphill, and others emphisize carrying momentum at high-speed through sweepers w/o much elevation change. the best tracks are a mix.

    restricting power beyond 85% tends to cause massive loss of Tq at high RPM, which is where most cars need to stay to take full advantage of gearbox ratios. BHP can't do the job alone at high speeds due to frictional and aerodynamic drag. you need a good mix of both for best overall accel in actual racing.

    in a straight-line comparo... if you take the same car, gear them the same, the one with massive Tq will blow the other away only when starting from low speed in high-gear. if you allow both to start in 1st gear and wind all the way out to redline through top gear, the one with a balanced drivetrain will win, all else equal.

    in actual race environment with corners, bumps, slick spots and elevation change... i agree that some cars perfom much better than others, and believe it's due to several reasons: tire contact patch, dimentions of the car, aerodynamic efficiancy, chassis capability and so-on. all of which give a natural advantage to a supercar detuned to race against suped-up passenger cars.

    i think each car has a BHP/Tq sweet-spot where all other aspects of the car's build can make the best effective use w/o overpowering or under-utilizing. the trick is to match this to the PP of the race, and match the car's handling strong points to the track.

    if knowing these things and selecting a competitive car based on them is an exploit, then maybe PD should make Sprint ( http://www.youtube.com/watch?v=RdVAUCpVv4o ) instead so everyone is equal.

    i'd rather have fun/tight races than focus on winning everytime at all costs, and knowing my car is dis-advantaged actually pushes me to drive better/cleaner.
     
    Last edited: Jul 13, 2011
  11. watermelon punch

    watermelon punch

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    Operative word being "heavily".
    Of course not every car will benefit from being heavily power limited.
    There is definitely a "sweet spot" for most cars, and it's generally not at "full restriction".

    But they all benefit from SOME level of restriction. And always do better with SOME restriction rather than NO power limiting.

    And if you take a race that's restricted to say 450pp... you will ALWAYS make out better by taking a higher PP car and using the power limiter, than taking a lower PP car and just upgrading it to the PP & not using the power limiter.
     
  12. Thaddaeus

    Thaddaeus

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    as the power band is not affected by de-tuning a car, de-tuning has to be in lets say a 5% ratio to keep it fair.
    If you detune a car by more than 5-10 % you are getting an "unfair" advantage. (given that the drivers are on the same level)
     
  13. watermelon punch

    watermelon punch

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    Yes I'm sure this is a good rule of thumb, given cars of the same class... with de-tuning without upgrading first.
    But most people don't do that. They don't just de-tune. They tune up, then de-tune back down. Depending on the "sweet spot" of power limiting, this can also interfere with the "fair" ratio.

    My point is that at whatever given PP, with free tuning... it's always better to choose a car that's already near that particular PP #, and then upgrade it and restrict it back down... Than to take another car that starts under that PP#, and then upgrade it upwards... even if you then restrict it down, but especially if you don't.
    Simply because sometimes the car is just naturally better at a given PP... say it's stock design is to run at 200hp... You might make it 350hp, but it will not handle as well at 350hp as a car that was designed to run stock at 350hp. The same applies to PP.
    If you look to race in a 500PP race... Do not get a car that's 440pp and upgrade it and think power limiting will necessarily help. It may not. This will not be as competitive as a car that's stock around 500pp, upgraded, and then power limited back down to 500pp.
     
  14. Thaddaeus

    Thaddaeus

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    sure, if you take a car which is already over a given limit and tune it further it will most probably handle better with the power plus than a car which started way below.
    This is mostly due to lets say a Ferrari beeing already designed, or better designed for a certain amount of power/speed as a Fiat.
    With a custom suspension LSD, etc. you can cover up for this "mostly" though if you know how to tune correctly (which i dont :p).
    Its a flaw in the game design however. The powerband for each car needs an algohythm to simulate or realise the limiter better. The way it is currently implemented is just lazy programming". (Whereas im not blaming PD here, rather the Publisher!)
     
  15. Inferno251

    Inferno251

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    I think this is true, because if you add a turbo to a car, for example, and detune it to its original layout, the turbo is still going to work.
    One thing the car settings menu needs is to give us the ability to create sets to allow us to switch from one tun to another easily, rather than wasting time on tuning the car from your settings to completely different settings and back again.
     
  16. Krazie Ivan

    Krazie Ivan

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    completely agree. :tup: my concern is hearing alot of (paraphrasing here..) "using the Power Limiter = auto win". no matter how wrong an assumption is, if enough people believe it, the knee-jerk reaction might be a lack of online lobbies allowing the Power Limiter if PD gives us the option to disable it. lack of variety in the field would soon follow. :tdown: lotta "if"s, but easier to catch the snowball at the top of the hill.

    Power Limiter is a double-edged sword... it can provide an advantage just as easy as a dis-advantage, depending on how ya use it.
     
  17. shirakawaa

    shirakawaa Premium

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    PD should make the "power limiter" work like real life intake restrictors, which generally decrease torque exponentially with rpm (how much depending on how restricting is the flange). Here's an example of how it would work:

    [​IMG]

    Solid curves = normal engine
    Transparent curves = intake-restricted engine
     
    Last edited: Jul 13, 2011
  18. Inferno251

    Inferno251

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    ^^ Future update, maybe?
    It is a better, more realistic idea you have Shirakawa
     
  19. shirakawaa

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    I hope. However my conclusion is that most of the PD staff (except maybe for the guy in charge of programming the physics engine) and that means Yamauchi included, doesn't have a clue about how cars work in real life, and therefore things like a realistic implementation of engine restrictors have slim chance of being implemented in future updates.
     
  20. Morgoth_666

    Morgoth_666

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    Well then at least they're consistent, they know as much about cars as they do about racing. :)

    Your idea sounds like exactly what everybody wants, btw.
     
  21. shirakawaa

    shirakawaa Premium

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    I've added a zip file with the spreadsheet I made in case anybody wants to experiment around with the extremely simple algorithm for power restriction I used to make the previous chart. If the chart looks bad it's because the spreadsheet has been converted from .odf format (LibreOffice) to .xls (Office).

    EDIT: by the way, actually in real life the loss of torque and power at high rpm would probably be a bit less dramatic as the engine's intake is restricted (this fact would be counterbalanced by a more generalized added loss of torque at all rpm), but you get the idea. Even after adding such corrections, that would still be simpler and more realistic than PD's current implementation.
     

    Attached Files:

    Last edited: Jul 13, 2011
  22. VBR

    VBR Premium

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    Only PD could make a power restrictor that made the car more powerful!


    :lol:
     
  23. shirakawaa

    shirakawaa Premium

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    By the way, I'm sorry if it's drifting the topic away, but with the spreadsheet I posted previously, I tried "restricting" NASCAR stock car-like power/torque curves to the power levels of what would happen in real life with a proper restrictor plate (left chart). The chart to the right is approximately what happens currently with the power limiter in GT5:

    [​IMG] [​IMG]
     
  24. Exorcet

    Exorcet Premium

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    Thus, we should avoid hp limits and use PP because is negates the problem totally. The limiter is completely fair, and using it to extremes will only bring you disadvantages because you'll lower your average power per gear.


    Power limited cars always have less hp than non limited cars of the same PP.


    It seems that the people that know about are at more of a disadvantage. A flat power curve doesn't matter when it's wider than your gearing. If you make 350 hp from 0 to redline RPM and your gears cover 5000-8000 RPM, you will never beat a car that makes 25 hp from 0 to 5000 RPM but 400 hp from 5000 to 8000 RPM. Set your gears properly, and use manual transmission. Flat powerbands should only result as a last resort when you're trying to cram a 700 PP car into a 400 PP race.
     
  25. shirakawaa

    shirakawaa Premium

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    There are several cases, however, where an hp limit makes more sense than a PP limitation in GT5. That's mainly racing on fast tracks, where light and nimble cars short on power with the same PP rating are clearly in disadvantage against heavier, more powerful cars.

    Using PP limits instead and avoid using hp limits should be a temporary measure. My opinion, as I stated previously is that PD should make the power limiter work more realisticly, like real intake restrictors used in many sanctioned races. While it would not eliminate the problem completely (as long as different cars race together, there are going to be technically faster ones), it would render its use more fair and less prone to "exploits", not to mention more realistic.
     
  26. Exorcet

    Exorcet Premium

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    Well that's the driver's call. I don't think I've ever used power limits since the release of PP. At first I was tempted to use them for Super GT races, but because PD modeled the air restrictors and weight penalties on those cars, it just makes some cars too dominant, especially the lighter ones.

    Even with more realistic limiters, the lighter cars will still lose on the high speed tracks. PP would need to account for the track to fix that, though I don't really think it's necessary.
     
  27. grog

    grog

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    So this topic/subject has been floating around for a while now, has anyone posed this question to Kaz or PD through twitter or whatever.
    Or is there something in the feedback section addressing this?

    I would ask but Im not a twitter user.
     
  28. watermelon punch

    watermelon punch

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    I don't know what you're trying to argue here?????

    Sure, lots of things figure into this. But if you don't know about this at all, you will be at a disadvantage.
    I'm not understanding how you think knowing about this puts you at a disadvantage. That sounds crackers! :crazy:

    Not only that, I never said anything about flat power bands. I'm simply talking about improving torque & the power curve, in general, by using the power limiter. (Flat or not flat, or whatever, there's always an improvement over not using the power limiter.)

    Here are 2 examples:

    You join the Low HP League. You go about choosing a kei car to use. The restrictions are 98hp/700kg. The tracks are mostly short & tight - like Tsukuba, Madrid Mini, London.

    If you upgrade your kei car with mod parts to bring it JUST to 98hp, you will NEVER have the same kind of torque the rest of the racers do by slapping on various upgrade mods, and then power limiting down to the 98hp.

    You decide to race the Triumph Spitfire series... The restriction is 108hp/810kg.
    If you simply upgrade the Spitfire with mods to bring it just to 108hp, you will be at a disadvantage against people who are using the power limiter.
    Not only that, but 810kg is the stock weight of the Spitfire. And many of the racers weight-reduce the Spitfire below that, and then add a bit of ballast back to use ballast bias to help the car be a little more stable.

    I don't care what kind of gearing you use, or if you use MT or AT. If you don't use the power limiter in these situations, you will NOT have the kind of torque... your car just won't have the "go" that people using the power limiter are getting.

    So no, I don't think this power limiter "trick" just applies to cramming a 700pp car into a 400pp race. (If that's even possible or wise.)
    It applies across the board.

    So I don't know why anyone would say that people who know about this "trick" are actually less better off. :boggled: :rolleyes:
    Why would you even say something like that?
    You really think that NOT knowing the power limiter trick gives you an advantage? :lol: :rolleyes: :boggled:
     
    Last edited: Jul 13, 2011
  29. Exorcet

    Exorcet Premium

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    Sorry for not being clear. I'm saying that the limiter is misunderstood. People all seem to be assuming that going with the power limiter leads to domination online. So I assume that most people are super tuning and then limiting, but it might just make then end up slower. I'd really like to see a thorough test of the limiter to see which side is actually right.

    Is this offline? If so, it's not really a concern. Even if it was online, the rules say 98 hp. So long as you make 98 hp, it's all fair. If the host wanted to give non limited cars a better chance to compete, PP would have been a better choice. And if this race is a league race here on GTP, it's possible to use both hp and PP, and car restrictions to make the race whatever the host wants.
    Same as the above.

    I agree. But the problem isn't the limiter. It's people not using PP. All of what you say it valid under the hp and weight system, but vanishes as soon as PP is used.

    It was a figure of speech more or less, and again I apologize for confusing you. However, when most races online go by PP, and organized league races are able to use very detailed rules, I'd say it has a bit of truth. If we were back in the pre-PP era, then the power limiter would certainly be a dominant force.

    Also to further clarify, I did not mean that the limiter was a valid exploit or trick when trying to fit a very high PP car into a low PP race. I was saying that, the only time it's OK to have a really flat powerband is in that situation.
     
  30. Sohvakettu

    Sohvakettu

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    I think i saw a test done about this on one of the older threads. It used three NSX's, one tuned traditionally to the wanted hp limit, other overtuned and then limited back to same hp as the original and third overtuned and hp restricted to same pp as the first one. The hp limited was fastest, pp limited second fastest and the non restrictor tuned was slowest (done on Suzuka i think). Can't be bothered to find the original though so maybe i should try the same test myself some time.