Lateley i raced a whole weekend on wet astro turf due to occasional showers. It was pretty educational, because in wet conditions, the B74, or 4wd in general, tend to push a whole lot more into corners, resulting in massive understeer. My solution to this issue was to flip the setup compared to dry astro turf conditions.
- thin front sway bar, thick rear sway bar
- more front toe out, less rear toe in
- more front camber, less rear camber
- no front top plate brace
- front arms outward with 1° A block inserts out
These were changes that could have been easily reverted to get the rear more locked in, if the track would have been dried during the race weekend, which it didn’t.
Another important aspect when racing in the rain is to protect the car, especially electonics, from harm.
- treat the motor sensor board and sensor port with wet protect
- open the esc case and treat the boards with wet protect
- close esc openings with plasticine
- open the receiver an treat it with wet protect
- treat all metal parts that are not stainless steele, aluminum or titanium with wd40
- WD40/Oil/WetProtect/
A problem i was not able to solve has been lack of traction at start of the mains. The car was set up as light as possible, so maybe more weight would have been helpful to stay in front during the start on the straight. On high grip, the lighter car is definitely a advantage but on very low grip, in wet conditions, it seems to be a disadvantage, at least at the start of a main.