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Sports GT
03-07-2006, 04:57 PM
What does this mean?.. I've heard the term before but not exactly sure what it does... I've been told people do that and I don't know why.. when we opened my gearbox a friend of mine said my diff was welded... What does it mean and why is it done? and can it contribute to the horrible knocking I hear when I turn and the car feels like the 2 front wheels are turbing about the axle and different speeds.... does this have anything to do with LSD??

Axeboy
03-07-2006, 05:44 PM
You always see drift cars with a welded diff... ie welded to help drift.

So, not for us.

Maybe a weld repair on your car?

amsoil
03-07-2006, 06:09 PM
A welded diff has no place on a road car. It is just a cheap and barbaric way of converting a car a 'spool' which isnt a diff just a solid connection between each wheel. It is used in dirt track racing to allow the rear end to come out under control and power (but generally with differing size tyres (Stagger)). It is also used in Le Mans and Daytona cars because the tyre wear and handling probelms it causes (plowing or very bad understeer) is compensated for by the hourly change of tyres, and the get you home value of being able to drive back to the pits with a drive shaft ot CV joint broken.
The only place I could imagine this to be in a VR4 is in a diff between front and rear to give fixed 4 WD ; otherwise the car may well be undrivable on the road. :inquisiti

Lucas
10-07-2006, 08:37 AM
I can't really explain it in 4wd terms but...

For example, when turning a corner, the outer wheel will turn further than the inside one. A normal diff will allow for this difference in rotation while still supplying torque or driving force to each wheel.

If your diff is welded, both wheels will be 'locked' together and turn at the same rate - not good for gripping the road. If both wheels are locked together then you will find one wheel (possibly both) will be dragged when you turn corners hence the excessive tyre wear and poor road holding capabilities.

Rotary heads love this as it makes for much better burnouts (same as drifters for sliding). If you watch a car doing a burnout you will sometimes notice that only one wheel will spin rather than both, this is the differential 'slip' and the one that is not spinning will still be driving the car as normal resulting in a pathetic burnout.

In terms of a 4wd it is similar but it's kinda hard for me to get my head around. :book: :thinking:

You say it feels as though the car is turning around your diff as the centre point. YEP!