ok so i know the hicas vlsd is a 1.5 way but i heard its not really good for drifting. Which is why everyone welds their diff i suppose but anyway would a 1.5 be good for like road racing? Why isnt a 1.5 way good for drifting anyway?

VLSD units take longer to engage, and are prone to over heating the fluid, and usally have a limited amount of tourque they can hold from a side to side split. They aren't bad per se, they just aren't the best. Better than an open diff, but that is about it. Not sure if a 1.5 is bad for drifting or not. a 1.5 diff means that it has a partial engagement on decelleration. I guess drifters use 2 ways?

A welded diff is about the cheapest route, and ensures that both wheels are always locked together.

I am not sure if drifters don't like a 1.5 way diff, or if it is the viscas part that they don't care for, or maybe both. I don't drift, so I can't really say.

Some road racers use VLSD (Think Spec Miata on a budget). But typically, a HLSD or a CLSD are better units by an order of magnatude.

I use a VLSD, but it is that or an open diff for my car in the class I run in. Like I said it is better than an open diff, but I would rather have a HLSD.

VLSD works off of the diff fluid. The silicone particles in the thick fluid allow the gears to lock up. As heat gets to it, the silicone particles break down making the "lock up" not so efficient. Basically, after you've been running your vlsd hard for a while, the diff fluid gets too thin for it to lock up, and it makes it feel like you're running an open diff.

drifting with a 1.5 is do-able, but you'll want the constant lock when decel (when your foot is off the gas).

Drifting is all about throttle control when breaking traction. It doesn't mean stepping on the gas the whole time and hoping you won't spin out or anything... thus why a welded diff or a 2-way is better intended for drifting (constant locking of both wheels on accel and decel).

but what if you want something daily drivable? i heard that the 2 way is very noisy and also sometimes locks when you dont want it to. is the 1.5 way clutch type? or are all 1.5 ways viscous and all viscous 1.5 ways? also i'm not understanding what is meant by the diff locking under deceleration, does this mean that the wheels actually spin backwards?

The diff locking under deceleration (or the LSD engaging on decel) means, when the car is slowing down the diff locks. Just like it does when you are accelerating.

1 way dif: on engages on accel1.5 way diff: engages fully on accel, and partially on decel.2 way diff: engages the same on deccel or accel.

So if you have a 2 way diff it will "lock" the wheels when you are slowing down, just like it would when you are speeding up.

viscus has nothing to do with the diff being 1 / 1.5 / 2 way.

A VLSD uses fluid to "lock" the two wheels togetherA HLSD uses gears to "lock" the two wheels together. Personally I love these types. But one word of cation, if you unload one wheel completely (On ice, or off the ground) it will revert to an open diff, due to how they function.A CLSD uses clutch packs to "lock" the two wheels together. When people talk about noisy diffs, it is the clutch packs engaging that makes the noise. Although the Helical unit in my Spec-V did make a nice whine at low constant speeds in first gear.

About half way down the page.http://www.carbibles.com/trans....html

Most clsd you can get in any config you want. I think hlsd are usually 1.5's but I *THINK* you can get them 1 or 2 way. Not really sure on vlsd.

Pretty much anything other than a welded diff is daily drivable. As far as it engaging when you don't want it; once you know what the car will do under what type of circumstances you probably won't notice it, or plan accordingly and drive around it. Although I could see how having the diff lock up on decel when trying to make a sharp turn with something on the outside of the turn could get interesting.

HTH

so the term "lock" simply means both wheels are moving at the same speed right? so if i get a 2 way clutch type lsd, and i want to grip in the canyon is it still a possibility. because i'm not understanding how both wheels spinning at the same speed effects grip in a turn. i mean i guess since the outside tire is under more strain then the inside that could have something to do with it but if thats true than wouldnt a 2 way diff be ineffecient for anything but drifting? i'm very confused...

"Lock" is some what of a misnomer. Unless of course you are talking about off road 4X4's.

There is a reason they are called LIMITED SLIP differentials. Because they LIMIT the amount one axle can SLIP (Spin) in comparison to the other. When you drive around a corner at normal speed, the outside wheel needs to turn more than the inside. Under normal conditions with any kind of differential this isn't an issue. but if you have either no diff, or a locked or welded diff, then the outside tire will be forced to turn the same rate as the inside. This is why if you have every driven a vehicle with a locked /welded /sold diff/axle, the vehicle is very hard to turn and one or more wheels will skip, studder, bounce, ect until you complete the turn.

Now, on a power on, or slick condition, the limited slip comes more into play.When one wheel starts to spin excessively more than the other, the limited slip detects this, either manically, or via sophisticated electronic dohickys.Now, this does not mean that with your clutch LSD that when it engages you will now have a "LOCKED" diff, what this means is, that your tire that wants to spin free is limited to a portion of the force delivered to the other axle. This wheel may spin more, than the other, but it is not free to roast the tire, while the inside wheel continues on as if there is nothing going on. When a LSD engages, it doesn't so much slow down the axle that wants all the power, but it diverts a portion of the incoming power to the wheel that is still in full contact with the road surface, and otherwise not receiving any power. otherwise the outside wheel would get all of the power, while the inside wheel would get none. And that is why it is a LIMITED SLIP differential

Ahhh **** it, read this (BTW, this took about 5 seconds to find with a google search)Clutchhttp://auto.howstuffworks.com/differential4.htmGeneralhttp://www.howstuffworks.com/differential.htmWhat is a diffhttp://auto.howstuffworks.com/differential1.htmOpen Diffshttp://auto.howstuffworks.com/differential2.htmDiffs and tractionshttp://auto.howstuffworks.com/differential3.htmViscous Diffshttp://auto.howstuffworks.com/differential5.htmLocking and torsen (helical, gear)http://auto.howstuffworks.com/differential6.htm

Plus the other link, in my previous post.

Note for Google reviewer:

Where is the "Dangerous or derogatory content" in this thread that has someone so concerned? What policy violations must be fixed here?