What is the difference between Posi, and limited slip? My car is a G92 car, it's a limited slip right? Waht's the difference between a spool, and a locker? Would a new posi unit be good for my car, or a power trax locker? I'm also swapping to 3.73 when I do it. Which one of the 4 is most liveable with daily driving due to incliment weather, I need to have an idea.

 

Possi and Limited slip are the same thing. GM's name for limited slip.

 

A Posi and Limited-slip are the same exact things. GM coined the name Posi back in the '60s.

Now as for a spool.....there is NO mechanical action associated with this type of unit. Both axles are basically connected through a strait splined carrier. Which means both tire are going to turn the same rate, but you will drag the inside tire through a turn.

As for a locker.....it is similar to a spool, BUT it can differentiate (allow the inside tire to turn its smaller radius) if no power is being applied. The difference between a posi and a locker is the posi uses a clutch type friction medium to apply power to both wheels. The locker, if you are accelerating or decelerating will turn both tire the same rate, but in a "float" condition the axle will differentiate or unlock mechanically.

You have stated that you dirve in incliment weather, I would not recommend a locker in your case. Water, snow, slush/ice you will find yourself driving sideways more than you will ever want to. But in a dry climate or with a car that will be primarily driven in a strait line, this will be a good thing.

IMO, an Eaton limited-slip differential would be your best choise. It can be tuned and re-built, something none of the other choises have to offer. They used to come in the 12 Bolts back in the day ('60s) and I use them in all of serious build ups.

Another choise would be a Thorsen/Gleeson (aka Torsen). Great product but not as strong as an Eaton. It is a torque sensing type differential, which is used in road race cars and some production cars. There a little more expensive, but every now and then you can get one on sale at SLP.

 

Thanx! So has anyone ever used a Torsen, or a Power Trax? I don't know if my Z will be daily transportation for long, so......

 

I've used both but will let someone reply first.

 

 

Powertrax for 6 years. Street driven 99 percent of the time. No problems here.

 

Torsen in sig. Uses gears instead of clutches like the other posi's out there. That and a good price convinced me to buy, and I have had no complaints since it was installed