spool diffs

[travyMX5]

ok...anyone use a spool diff in their car??
obiously it would b ok for track but does anyone use them in a street going track car??
pros cons ect??
thank u

[Sheck]

I dont use one, but they are illegal and would be a bit sh*t to drive with on road and very dangerous in the wet.
I've had 'real' LSD's in my car since i got it except for a month during an upgrade from 1.6 to 1.8 diff. Very effective and one of the best mods you'll ever do, need to change the diff oil every time you change the engine oil if you want it to be properly maintaned tho.
If your considering a spool then you'd be best to stay away from a torsen (as an alternative) cause they are weak (abuse wise and locking capability ie wheel lift)

Dave

[stevesports]

by spool you mean locked diff?

in that case it is generally rubbish on handling since both wheels are turning at the same speed.

In addition, it becomes very scary once you get the rear spinning since both wheels would have lost traction, rather than one spinning whilst the other still maintains some form of grip.

locked diffs would be briliant on the drag strip though, but for everyday use it is tricky to use.

[Blue94t]

I used to drive lockers on the street all the time.
As long as you respect them and know what to expect they are fine. They do make the driving experience a bit harsher.
As far as handling goes they require a slightly different car set up and driving style but they can be made to work very well especially on the track.
I seem to remember reading on here that the dedicated track MX5's in Qld often run spools.
Nothing wrong with a well set up spooled car except the illegality of driving it on the road.
Jake

[Hellmun]

Unless your running big power I wouldn't do it. You get understeer with a standard clutch-pack diff....Unless you need both wheels to power out it doesn't seem worth it. I think my car would actually be faster with a torsen. I'm running 91kw atw but once I've got the car turned in...most of the time as long as I dont' stomp the pedal..I'm full throttle before I hit the apex and am the whole way out. Semi-slicks + clutch-pack gives me more grip than I need on the way out but understeer on the way in if I'm slightly too fast and then I have to trail brake.

I guess the bad aspects of my car is that the diff is very shuddery, reverse with full lock cold and the car will shake a lot. You drive too fast in the wet you better be awake, you will be snapping out much faster. You have a higher limit but if you surpass it you will be punished much harder. Spool I imagine would be worse as atleast I have to put my foot into it to make it unstable.

I guess on the positive side..the clutch pack diff means that though I have a wheel airborn while getting up my driveway..the Tomei actually locks. The Torsen wouldn't...so I would have to reverse up all the time. Spool also has this advantage.

Also expect a spool to be very noisy in normal driving between trackdays. You will have squeling rubber a LOT everytime you turn so don't think it'll be subtle if a cop is behind you.

[irwin83r]

not to mention car parks make the wheels shudder like crazy with a spool as the inside wheel skips and skids having to do the same amount of rotations as the outside wheel. not too bad with a clutch pack however...

[zoomzoom]

Depending what you are planning to use the car for just get a good lsd. If it is a roadcar or track car get a torsen, they grip beautifully and bias the torque to the outside wheel which helps unbelievably during cornering, it absolutely transforms the car. If you want a roadcar that can drift or drop fooli sik skids then get a normal lsd. If you are using it as a track drift car or something like that then go a spool, but they will probably not be the best at anything else. If you are cheap and like the spool idea then pull the diff and make it a CIG locker!

My 2c, Tim

[Blue94t]

I've said it before and I will say it again. Torsen's are great for NA cars but my experience with my turbo Clubman is the factory torsen is unpredictable and useless if you lift the inside rear wheel on the track. Sometimes my torsen would behave like an open diff on the street.
It did it once when I was taking Green_Comet for a ride.
Get a good clutch pack LSD if thats the way you want to go. They are consistent and predictable.
Other wise go the spool. They certainly can be made to work very well