RR, I’m going to have to respectfully disagree with you.

Arbs do not know whether you are on throttle or off, and would greatly effect transition (lateral) stability much more than a diff would, unless in transition you are highly modulating throttle/brake at the same time. Arb’s are effective at all speeds not just low speeds you may seem to feel the effects at low speeds but they are always doing something. They also effect general responsiveness which may be why you are noticing there effects at low speeds the best.

Diff controls off throttle or under braking, regardless of what speed you are going. You may notice its effects more at mid to high speed because like everything the faster you are going there is a multiplier on the effect. Surely you are going to feel a car rotate more if you are doing 150mph and decide to let off the throttle and go to full lock, than you are at 20 mph.

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Yes, it appears you are right. Great thread by the way.

PTG Baby cow: It was fixed as in the rear of the car wouldnt slide out when entering a corner.

PJTierny: I also noticed something similar with the lancia beta racecar on catalunya national where at the top of the hill with the high speed sweepers that a lower decel setting made the car quite understeery through there while a higher setting could make it lose rear grip very easily on entry.

GSR RoadRunner: I was only changing the diff decel when i noticed these changes with both cars.

It should be noted as well that a lot of the effect (or seemingly lack thereof) as it pertains to differential settings are heavily influenced (at least in FM6), by both TCS and STM.
I generally have been running no TCS (lately I have been employing STM as it helps with minimizing the effects of incidental contact and keeping the car ‘in-line’ as I race using a wheel and not a controller). Running TCS on gives a lot of flexibility in differential settings (accel side)…as the adverse effects of a high setting go un-noticed.
I see a lot of folks that use really high accel settings (70% or more), which to me in most cases is unbearable as this leads to a lot of throttle-on over steer.
In support of Baby Cow’s post above, ARB’s heavily influence transitional over/under steer, and setting problems become more evident in higher speed sweeps and transitions (Bathurst, Road Atlanta for example). I always try to avoid drastic differences in the front vs. rear…I prefer anti roll in a ‘neutral’ state across the entire wheelbase. Seems to me if you can get your springs and damping set ‘right’, ARB’s and differential do not need to be modified as drastically. Of course there are exceptions to every rule, and everyone tunes according to preference…but based on my experience the fatal flaw is always radical adjustments in one area to compensate for incorrect values/settings in another.

Agree with PTG BC & BW.

BW, your comments regarding making radical adjustments in one area to compensate for another is absolutely right. If radical adjustments are needed in one setting it usually is compensating for a larger problem elsewhere.

My approach is always:

  1. SPRINGS = General Characteristics
  2. ARB = Cornering Balance
  3. DAMPERS = Corner Entry/Exit Transitional Behaviour
  4. DIFFERENTIAL = Power On/Off Behaviour

AWD, is a different beast altogether. It’s a combination of FWD & RWD and has advantages & disadvantages of both. The advantage is in its stability and ability to accelerate very quickly from low speeds. In this respect, front-rear power balance is key to a well cornering AWD. I think fast rotating rear + good pull from the front strategy would work well?