Little annoying that he had multiple people trying to help him and he left and didn’t explain what fixed his problem, but I’m going to give him the benefit of the doubt that maybe he changed a bunch of things in tuning and doesn’t realize the specific minor issue causing the problem.
As several people have noted it could be, it is absolutely the brake bias. Cars such as the 05 M3 come with a default brake bias of 40% which will make your braking extremely unstable imo. The way I see it, ideal brake bias tuning would be tuning so you don’t ever get noticeable understeer when braking in longer braking scenarios, but that your car doesn’t start dipping and oversteering for you.
If you don’t want to mess with it, just go 50/50 and you’ll be good. Otherwise, 50% and then adjust rearward slightly til it starts to pull on you more than you like.
Brake bias is one thing to check (I had the same issue you and others have noted with the '05 M3 - moving it forward to right around 50/50 did the trick).
I had a similar issue with the (AWD) Golf R that i used for one of the very first series. Turned out to be the differential setting. IIRC, the default tune had the split between F/R to be around 90/10. It’s my understanding that this should have just caused it to behave like a FWD car, with minimal help from the rears. You would think this would induce normal FWD behavior and the car would tend to understeer under braking. But for some reason it was causing the rear to want to overtake the front, especially under heavy braking. Confusingly, what sorted it out was moving the F/R split from 90/10 to somewhere around 50/50. I would have thought that doing this would give it more RWD characteristics (namely off-throttle oversteer), but like i said, it cured the problem and now it brakes straight and true.
I hesitate to call it a bug, as I don’t remember the exact specifics (I could be misremembering something), but the solution definitely did not seem intuitive and was not what i expected.
You need to change brake bias in tuning. But in order to do that you have to unlock the ability to do it for each car. It may take 1 or 2 races to do this.
A lot of cars are undrivable until you do this.
What a stupid system. This is not fun driving something uncontrollable.
This upgrade system was obviously designed by the work experience kid. A normal person would have seen the short cummings of this.
Starting a new playlist is not fun knowing a car will be undrivable for a couple of races.
The wheel definitely seems to need some different tuning. On controller I was using 45% (45F/55R) for the FWD Honda intro spec series. On wheel I had to switch the other direction to 60% (60F/40R) to get it feeling similar.
Also, check if your wheel has any way to do a “brake curve” or “brake pressure”. I had to turn mine up about 20 points from default to get more of a curve so the sensitivity is much lower at the beginning of the brake. Mine was very “shabby” and adding this brake pressure helped even the feeling out.
Do you use anything lower than 900 degrees rotation ? I ask because cars get very twitchy to drive with way lower than 900 degrees on the wheel. The lower the more tricky especially under braking.
450-900 depending on the car is ok. But you never know and i have seen many people driving with 180 or 270 and wonder why cars drive and handle like very badly.