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Discussion Starter #1
For those of you who have experienced wheelspin..... :lol:

Do both front tires "always" spin at the same time and rate, or is it a constant balancing act between the two tires i.e 60/40 than 40/60 kind of thing??

I was also curious if the LSD is adjustable?? (guessing not) I'm reminiscing the days of 1/10th scale stuff and you could adjust until the cows came home using different weight oils or tension settings etc.. etc.

Cheers!
 

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I'm not entirely sure about the LSD on this car, but i'm pretty sure it's a fixed rate mechanical, basically meaning, you can't change it. I haen't had enough dry road to lay down some treads, but i'll let you know what the burnout looks like when I do.
 

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when I spin, I spin 2 tires, cant tell ya much more than that. There is virtually no torque steer, so I gotta imagine both are gripping or slipping at the same rates.
 

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Im at the point of spining both and having near monster toqrue streer.....LOLO...but thats expected as you add power to a front wheel drive car...
 

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So here is how an LSD works. Parts of it are similar to AWD if that helps anyone, but its not the same thing, before anyone starts yelling that I don't understand the difference! Oh, and most AWD systems use at least one LSD. In short it is what controls wheel speed and torque split from side to side. I'm sure someone else could give a much better explanation, but I'll do my best.

There are a set of gear or clutches/someting in the LSD. Under normal load, no wheel spin, it will allow the wheels to travel independent of each other because the speed differences the outside wheel and inside wheel need to travel since they are traveling different distances through a corner. We all knew this.

Now as wheel spin occurs, here is what happens in a "normal" or open diff. as one wheel spins, the diff transfer more power to the spinning wheel, which makes it spin more. This = a vicious cycle.

In an LSD (there is more than one type/way to do this, but the end result is the same) something, ie a worm gear starts to resist when one wheel spins. This means it is limiting the slip of the spinning wheel and forcing the torque to the non-spinning wheel and keeping the wheel speeds similar. (You can feel this by entering a corner and rolling on the gas, you will notice as you roll on the gas that the car pulls a little to the inside of the corner. This is the LSD working.) So as the one wheel nears the limits of adhesion it start to spin faster and the gear resists it by pressure, forcing it to keep closer to the speed of the slower wheel. That is the diff limiting the slip, ie, the speed of the wheels. Now if you grossly exceed the traction limit you will cause both wheels to break free, when this happens, the diff will "lock" the two wheels together and the will travel the same speed. If you are going in a straight line, you will lay down two black strips of rubber. If you are turning you will have MASSIVE power understeer and be heading off the road toward the outside of the corner.

So thats my convluted explanation, hoped it helped confuse you some more :D

More info on LSD types can be found at the Wiki link below, but they did not seem to have a good explanation of what it meant when actually driving. The LSD is not tunable. There are adjustable LSD's but they are very expensive.

http://en.wikipedia.org/wiki/Limited_slip_differential
 

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the other day i went around a turn and put that baby to the floor with my dsc off and spun the tires. I was getting alot of wheelspin out of one tire and not so much the other. so i think its safe to assume that they both spin at the same rate.
 

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truered said it best. it only really comes into play in a wheel spin environment and helps equal the rate of revolution... thereby creating understeer in the turns and "almost" equal patches on the straights. i do like the lsd on this car even though its FWD...making it capable of handling higher torque levels before locking out both. so to answer the adjustable question... NO, but the car adjusts it about 60000 times a second when you are spinning the tires.
 

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Discussion Starter #9
perfect!!

I'm not going off the bend by assuming this car must get pretty much the same traction as a typical "cheap 4WD" system in the snow(assuming same tires). As the lower end 4WD systems usually allow one back and one front wheel to spin when their in no traction??? However I'm sure there would be a slight advantage having one wheel "push" and another "pull" vs. 2 wheels "pulling"....
 

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The LSD will help give you grip in slippery/snowy conditions over a standard diff. Especially if you can limit the amount of wheel spin.
 

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yeah... with the same tires that i had on my 05 mazda 3 s...... my speed 3 handled snow like it was a damn 4X4.... i never could get this thing to slide or anything else... i really had to try to do it! lol 6" snow in a football parkinglot is fun!!! :lol:
 

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[quote author=tvissues link=topic=71345.msg1258438#msg1258438 date=1173461550]
yeah... with the same tires that i had on my 05 mazda 3 s...... my speed 3 handled snow like it was a damn 4X4.... i never could get this thing to slide or anything else... i really had to try to do it! lol 6" snow in a football parkinglot is fun!!! :lol:
[/quote]
I'm jealous.
 

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[quote author=TrueRedSpeed link=topic=71345.msg1259243#msg1259243 date=1173491531]
[quote author=tvissues link=topic=71345.msg1258438#msg1258438 date=1173461550]
yeah... with the same tires that i had on my 05 mazda 3 s...... my speed 3 handled snow like it was a damn 4X4.... i never could get this thing to slide or anything else... i really had to try to do it! lol 6" snow in a football parkinglot is fun!!! :lol:
[/quote]
I'm jealous.
[/quote]
why so? summer driving is soo much funner! lol yeah i just typed "funner" lol
 

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[quote author=tvissues link=topic=71345.msg1261838#msg1261838 date=1173659865]
[quote author=TrueRedSpeed link=topic=71345.msg1259243#msg1259243 date=1173491531]
[quote author=tvissues link=topic=71345.msg1258438#msg1258438 date=1173461550]
yeah... with the same tires that i had on my 05 mazda 3 s...... my speed 3 handled snow like it was a damn 4X4.... i never could get this thing to slide or anything else... i really had to try to do it! lol 6" snow in a football parkinglot is fun!!! :lol:
[/quote]
I'm jealous.
[/quote]
why so? summer driving is soo much funner! lol yeah i just typed "funner" lol
[/quote]

So are snowy parking lots, was looking forward to it all winter, but never really did get enough snow or get out of the city. Snowy lot = free skid pad.
 
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