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Ok i Know a Ball diff is great and is standard on the top line kits.

I have been racing since 85 when ball diffs were very limited to the best of the best as standard equipment.

I have been asking myself this question for a while now based on track performance not HYPE. I have a Optima MID that i raced back in 88 with open diffs and still race it now in the same spec with no disavantage against a ball diff equiped Lazer. In theroy the ball diff acts as a limited slip diff but does it really help lap times.

My Mate pulled out his evo diffs on his top force for geared diffs from a manta ray with no affect on handling at all. Im thinking of playing with a geared diff in my Terra Conqueror to see what affect it has.

If None i will stay with a geared diff as they don't require rebiulds or slip.

I'm talking off road only.

Any thoughts on this with proper back to back testing ???

Thanks.

My personal feeling is that, if the traction is high, they are about the same. When it is slippery, I feel that ball diff is better because it would not 'unload' like the gear diff. But of course, with proper lubrication in the right viscosity, gear diff would not unload so easily as well

the ball diff can also act as a slipper/ torque limiter........especially during landing after those jumps & bumps......it can prevent damage to the drive train......

its a good question. considering all things being equal (gotta have a slipper) idk. i ran a sc10 and the gear diff was perfectly fine

In a 4wd it is harder to tell. Try it in a high HP 2wd and it is clear. I have an Optima Mid and it ran like a scalded dog. My T4 is different story. If the diff is too loose and it is a one wheel wonder it is a handfull. I would rather have a tight diff and drive with a drift to get the forward bite.

A Ball diff is not designed to be a slipper,

Any slip in a ball diff quickly destroys the balls and drive rings.

All A.E and Losi manuals state this.

A ball diff requires a smooth butter action to be 100%. As soon as that goes it becomes a pepper grinder. It doesn't take much to do either. A little slip here and there under full power. A little dirt in the thrust bearing. they are sensative .As soon as this happens you have lost any if any advantage you have.

Thats why a gear diff is more robust.

I really don't think there is a advantage in off road. A loose track nedds a light smooth diff to put the power down and not spin out on rotation changes.

I think it also depends on how technical the track is. The gear diff is heavier which means more rotational mass. People spend quite a bit of money to lighten every part of the drivetrain. If you need a lot of quick throttle commands a gear diff could hamper your times.