Why should I have a 4WD Front One-Way Diff Unit

[bjorklo]

Just wondering what is the pros and cons for a front One-Way diff unit? 

[Fabia130vRS]

As far as I know, 

for touring cars, a one way diff handles corners different, while turning without trottel, the one way glides without effort while the rear diff slowes down due to firction. as a drag brake.

or drifters use the one way for drifting, so while breaking (reversing) the rear tires block and stop turning while the front wheels keep rolling. 

I dont knwo if I explained it well above.

but a one way moves only forward, and tends to cut out the nose first understeer. Me also would like to know first hand experience with one way, as on touring cars, so on off roads too.

[Juls1]

You would only use a one way if you want increased off power steering, the one way disengages the front diff when coasting or under brakes. Meaning only the rear wheels can slow the car down. Given 4wd cars have more front weight bias applying the brakes often leads to the rear tyres skidding and allowing the car to rotate instantly. It’s useful on very tight tracks with a lot of switchbacks. 

Some people prefer it, especially bashers, I’ve not found any racing situation myself where I thought the lack of front wheel braking was helping me. 

[gizard]

I have one for the TT-02 chassis and have stopped using it - because as mentioned it makes the car spin very easily under braking - to be fair I have only used it on a buggy (TT-02B) not tried it on the TT-02R or TT-02 Type S I have - The R is currently setup for Rally so I imagine it will be just as troublesome as the TT-02B is with it. I think it is probably best with a very well setup chassis on a good grippy surface - something I don't use.... 

[Static Age]

As said, only any use on very tight tracks. I had one in my drift car but switched back to a locked front diff.

[Juggular]

I had installed one for TA02 Hummer.  I took it out.  Front wheels wouldn't reverse.  

Hummer could be the heaviest resin body for 4 wheeled cars.  Reversing with 2 wheels wasn't good for bashing.  

 

[TurnipJF]

I gather some people like them for rally use, where they allow one to emulate use of a handbrake on tight turns. 

[bjorklo]

Thanks for all your input, my conclusion from this is that i will not use one in my Top-Force, but i might in my ta-02 BMW. 

thanks again, you guy´s rock. 

[Mad Ax]

I have one in my Top Force Evo.  It came already installed, so besides removing it for a clean, I haven't taken it out.  It handled really well at the Revival 2017, in fact the car was a peach for the whole event, but this year's Revival was even wetter than last year and the lack of traction made it very touch with the one way.  As I'm not much of a regular racer I don't have boxes full of spares and option parts (although no doubt I could find a few new DF01 gear diffs if I hunted around hard enough) so I didn't bother to swap it out.  In retrospect I wish I had, I had a terrible weekend results-wise and being unable to brake for corners must have been a part of that.

I also have one in my D4CS drifter, the general idea being you can use the brake to initiate a drift without pushing the front wide.  It works just like a handbrake initiation in a full-size RWD drifter and it's a good way to get into the korogashi technique, although I've heard people tend to go back to a regular front diff once they've mastered it.  Since I don't get to koro my gashi much these days it'll be a long time before I'm ready for any two-way action.

[bjorklo]

So what i´m reading is that it could be wise to have one, all depending on track and weather.. I guess I should mount one and test under different conditions to see, when I should use one and not. 

Thanks for sharing your experience...