Gear diff or Ball diff..?

[Aire valley]

What are the advantages, one over the other..? What type of track favours one diff over the other..?
General "rule of thumb" guidance would be appreciated..

[Danny Harrison]

Originally Posted by Aire valley

What are the advantages, one over the other..? What type of track favours one diff over the other..?
General "rule of thumb" guidance would be appreciated..

General rule of thumb is that a ball diff is the better option in low traction, with similar performance in high traction.

Gear seems to require less maintenance is is much less prone to failing. Transmits more drive. Takes more time to make set up changes but is easier to reproduce.

Ball diff is probably easier to drive and quicker to fine tune. A little safer and less aggressive. Needs rebuilding fairly often and is harder to achieve the same feel every time.

[Oscar]

Originally Posted by Danny Harrison

Ball diff Needs rebuilding fairly often and is harder to achieve the same feel every time.

Really??
I don't disagree that once a ball diff reaches the "knackered" stage, it makes a difference to the car, but to say a freshly rebuilt unit feels different each time...
Maybe you are correct, but since starting racing in 1986 it's not an opinion I have formed

[Danny Harrison]

Originally Posted by Oscar

Really??
I don't disagree that once a ball diff reaches the "knackered" stage, it makes a difference to the car, but to say a freshly rebuilt unit feels different each time...
Maybe you are correct, but since starting racing in 1986 it's not an opinion I have formed

What i meen is, you are relying on 'feel' with a ball diff to set it, so setting it exactly the same each outing takes some fiddling.

With the gear diff, I know that putting 10k in will produce the exact feel it did last time, no messing.

[NeilRalph77]

Does the viscosity of oil not reduce if it's driven for a long time? so if you'd run 10k for a while without changing it and then put fresh in it would feel different anyway? Thus negating your argument.

But yeh generally ball low grip, geared high grip

And a well built well set ball diff doesn't require rebuilding that often!!!!

[Danny Harrison]

Originally Posted by NeilRalph77

Does the viscosity of oil not reduce if it's driven for a long time? so if you'd run 10k for a while without changing it and then put fresh in it would feel different anyway? Thus negating your argument.

But yeh generally ball low grip, geared high grip

And a well built well set ball diff doesn't require rebuilding that often!!!!

It doesn't if your putting fairy power through it

Just going on my limited experience, I'm sold on gear diff. The viscosity will change over time, but each rebuild will produce the exact same feel. Mine have been going 2 months since last rebuild and are still dead smooth.