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    Different types of LSD

    Another one to share

    In USA, all the FWD Honda's with the exception of the Integra Type-R and the new Prelude SH with ATTS are offered with any type of limited slip differential. The Civic Real-Time 4WD Wagons came with a viscous coupling center LSD, and the Acura NSX also has LSD (clutch type I believe).

    Differentials allows the wheels to turn at different speeds. They are essential in street cars for drivability especially in low speed turns. Under most everyday driving conditions, the standard open differentials works just fine. How ever, if one wheels starts to spin such as slick surface or when you are trying to power out of a tight corner, the spinning wheel would keep on turning power into smoke unless you back off the gas pedal.

    There are mainly three types of LSD - viscous coupling, clutch pack, and torque sensing (Torsen). Each type has their pros and cons.

    Part of this was from a post relating to the IS300, someone was asking about the difference between the LSDand the VSC option on their car... I figure i would share, because some of you out there may be interested. This is not technical by any means, but it is a good start to be able to tell the difference between the two.

    Im just going to take a stab at this, but if VSC is similar to other anti-skidding systems found on other cars thisshould be informative.

    VSC is used to control understeer and oversteer, which is by definition the car skidding. Understeer as you know is when the car is losing traction up front, most commonly associated with front wheel drive cars. While rear wheel drive cars have the ability to power oversteer. Understeer is easier to control IMO, and is safer. Some reason for losing traction are as follows, power to overwhelm the tire\'s traction causing it to slip since there isa thing called a traction circle, or transfering weight off from the tires in question..less weight = less traction. It controls it by applying brakes to individual wheels in order to manipulate load and correct the error. Understeering can be solved by application of brakes because it throws the load up front, more load, more traction. If your over anxious and powering through that hairpin turn, your going to power oversteer the car, so VSC i would imagine limits your throttle and cuts back so you don't spin the rubber and lose traction. Basically it manipulates load transfers.

    LSD - Limited slip differentials are used instead of open differentials for performance reasons. When you turn, the inside wheel has little weight on it as the load transfers to the outside wheels. With an open differential, the power will go to the wheel with the least resistance (the inside wheel), and it will just spin, what do you get? nothing. Ever notice those cars that do burnouts at a track to warm up their tires, and sometimes only ONE WHEEL SPINS, that's an open differential. Limit-slip allows the car to sense which wheel is slipping and transfer power to the wheel (in increments) to the wheel with the resistance. I guess you can say "from the wheels that slip to the wheels that grip".

    Kinds of LSDs.

    Well there a few kinds up there, helical, viscious, active, viscious coupling and im sure a couple more since they all have variations. Some require clutch plates and gear oil as regular maintenance, breaking, while some of them just "bolt on" and drive. The former would be a mechanical LSD, and the latter, a helical LSD. Which one is better? Beats me, just like most questions like that, "it depends".

    1.5,2 way LSD.

    Ok, well a 1-way LSD only is active when its moving in one direction. and that happens to be while your accelerating. When you are off the accelerator, your LSD will not be active, and thus the benefits for having one is nullified.

    1.5-way is the medium between 1 and 2, as the name may suggest, however, it\'s still not much better than the 1-way, because the 1.5way LSD, is particularly active when your on the accel. but let go of the gas pedal and you will find that the effects are very little.

    The 2-way, As you may have guessed, these are "better" than the 1.5 way because these remain active whether or not your foot is smashing the gas or the brake.

    Traction Control, in the simplest sense i can think of, basically cuts the power until traction is regained, this is from my observation on a few cars that had this feature, once they start slipping the engine pulls back and viola traction will eventually be regained.

    Launches, cornering will be improved with the use of an LSD. Because your not spinning as much and actually getting power down to the ground, not just using kinetic friction.
    Bad weather / sloppy driving will be assisted but the VSC however, i do feel that it takes a lot out of the actual "driver driving the car".
    Mugen Whore #2

    ヒール&トウのやりかた
    1)ブレーキを踏む
    2)クラッチを切る
    3)シフトダウンしなから、
      アクセルをぶかす
    4)クラッチをつなぐ
    :blah:
    インテ君と共に歩み続けて早1年・・・いろんな所へ出かけ楽しく過ごしてきましたが、事情により手放すこと となりました。(T0T)
    人生で初めて走る楽しさを教えてくれた「インテグラ TYPE R」・・・初めて走った時は何もかも衝撃的でした。今でも走る楽しさは変わらないですが。。。残念です。今 まで本当に感動をありがとう!

    #2
    i will just do the syntax/grammar check for you now...

    can you spot the glaring error in the first line?
    ... retired/

    Comment


      #3
      nah dave.....let me know......??
      Mugen Whore #2

      ヒール&トウのやりかた
      1)ブレーキを踏む
      2)クラッチを切る
      3)シフトダウンしなから、
        アクセルをぶかす
      4)クラッチをつなぐ
      :blah:
      インテ君と共に歩み続けて早1年・・・いろんな所へ出かけ楽しく過ごしてきましたが、事情により手放すこと となりました。(T0T)
      人生で初めて走る楽しさを教えてくれた「インテグラ TYPE R」・・・初めて走った時は何もかも衝撃的でした。今でも走る楽しさは変わらないですが。。。残念です。今 まで本当に感動をありがとう!

      Comment


        #4
        Originally posted by air23box View Post
        Another one to share

        In USA, all the FWD Honda's with the exception of the Integra Type-R and the new Prelude SH with ATTS are offered without any type of limited slip differential. However, the Civic Real-Time 4WD Wagons came with a viscous coupling center LSD, and the Acura NSX also has LSD (clutch type I believe).

        All differentials allows the driving wheels to turn at different speeds. They are essential in street cars for drivability especially in low speed turns. Under most everyday driving conditions, the standard open differentials works just fine. However, if one wheels starts to spin such as on a wet surface or when you are trying to power out of a tight corner, the spinning wheel would keep on turning power into smoke unless you back off the gas pedal.

        Kinds of LSDs.

        Well there a few kinds up there, helical, viscious, active, viscious coupling and im sure a couple more since they all have variations. Some require clutch plates and gear oil as regular maintenance, breaking in, while some of them just "bolt on" and drive. The former would be a mechanical LSD, and the latter, a helical LSD.

        1.5,2 way LSD.

        Ok, well a 1-way LSD only is active when its moving in one direction. and that happens to be while your accelerating. When you are off the accelerator, your LSD will not be active, and thus the benefits for having one is nullified.

        1.5-way is the medium between 1 and 2, as the name may suggest, however, it\'s still not much better than the 1-way, because the 1.5way LSD, is particularly active when your on the accel. but let go of the gas pedal and you will find that the effects are very little.

        The 2-way, As you may have guessed, these are "better" than the 1.5 way because these remain active whether or not your foot is smashing the gas or the brake.

        Launches, cornering will be improved with the use of any LSD. Because your not spinning as much and actually getting power down to the ground, not just using kinetic friction.
        hmmm
        ... retired/

        Comment


          #5
          Head of the class tinkerbell.

          Eddie: With/Without
          Official ClubITR Sponsor: www.autosphere.com.au - For all your maintenance, oils and track needs.

          Comment


            #6
            haha....haven't really read that.......sorry
            Last edited by air23box; 21-01-08, 12:53 PM.
            Mugen Whore #2

            ヒール&トウのやりかた
            1)ブレーキを踏む
            2)クラッチを切る
            3)シフトダウンしなから、
              アクセルをぶかす
            4)クラッチをつなぐ
            :blah:
            インテ君と共に歩み続けて早1年・・・いろんな所へ出かけ楽しく過ごしてきましたが、事情により手放すこと となりました。(T0T)
            人生で初めて走る楽しさを教えてくれた「インテグラ TYPE R」・・・初めて走った時は何もかも衝撃的でした。今でも走る楽しさは変わらないですが。。。残念です。今 まで本当に感動をありがとう!

            Comment


              #7
              pls read everything before posting!!!!
              ... retired/

              Comment

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