I have seldomly heard about using close diff. on the front axle on a RC car. What is the purpose to do that??? It is necessary to have a open diff. on the front axle during turning, coz the turing radius is not the same on the front wheels.
yes. some ppl like to use open diff at the front as the inner and outer radii of the turning in are different. however, it is also popular for ppl to use direct spool at the front cuz it can give u more power steering. so, basically, it is trade-off. e.g. both the new tamiya 416WE and the 415MSXX verison comes with front direct spool.
yes. i don't hv such problem when i was using front one-way in the past. however, there will be no front-wheel braking when using one-way. so, i constantly lock up the rear wheels and spin under braking. that's why i want to change to front direct spool lor.