@FST4RD...Loose the camber.
Try to get the front and rear tires the same diameter.
Set the car lower at the front then the rear.
When using the F103 tires at the rear, the car will become 200MM at the rear but still is 180 at the front.
This will cause a sharper steering car.
Try this(see pic) with the T-bar,it will help a lot.
Also do you run the steel ar carbon rear axle?
regards Roy