No wonder you can't drive this thing. Those parts are not good for usual driving. I think you just spoiled your car. It's the same thing with works converting car. I never know if this is good investment in some cases it isn't And you can't revers that process.
full up grades are fine for this car doing any type of driving, you just need to know how to adapt to each car and this car at b class in a legends race is a tool of a car, if your fliping it just sofen all your settings up, remember the car has old running gear will lots of power it hits 180mph easy so brake early and you will be just fine, good luck, 👍