WTCC Diff Setup Guide
Before making serious changes to your WTCC Race Car always remember that as a manufacturer they always get the weight distribution perfect right from the start, they know how the cars will behave overall at most tracks so maintain that car posture and also angle of attack(rake and trail) at most times as a base line. Due to the WTCC cars being FWD its worth noting that understeer is an integral part of this chassis especially if its got a turbo charged engine in it unlike naturally aspirated engined WTCC cars of the past because there was not a lot of torque mid corner only revs. In saying this we need to eliminate understeer by using the differential as a mechanism coming out of slow corners. Lets look at Diff Setting below,
Power - If you are understeering a bit coming out of the corner(mid) then lower the power value to create a more out of sync front axle to prevent the inside wheel from losing too much track grip while its already up in the air due to chassis roll. Now to further assist the diff in helping you get the car out of the corners faster you need to try and get the rear end pushing the nose down while maintaining a good level of grip at the rear, we do this by raising the rear of the car and adding 1 click of rear wing to balance it out for rear wheel grip incase someone tags you on the rear mid corner or you end up driving over a bump which unsettles the car. Increasing the power on the diff is meant for track like Monza where its a start stop nature.
Coast - Not much one really need to explain here, the higher the value the better because you are simply allowing more grip on the front wheel by relaxing the torque between then aiding in front turn in off throttle, if the value was lower you would understeer while off throttle in a FWD, I would lower this value in a RWD to help me turn in on fast corners by it locking the rear axle.
Preset- Once you have a great diff setting and you get to another track, instead of playing too much with the diff setting you can lower the preload for less understeer and increase it for more straight line lock.
Well I hope this was helpful and I will be doing more on other areas of the WTCC cars