My current Tamiya trf415msxx foam setup may help you understand foam tyre setups a little more.
28lb front spring 19lb rear.
Front - differential, 0 degree toe. 60wt 3 hole piston, 4.5mm ride height, 45shore 26mm enetti tyres, medium roll bar
Rear - differential, 3 deg toe in. 55wt, 3 hole piston. 4.5mm ride height, 42shore, 26mm enetti tyres, no roll bar
Additive applied to front inner half of tyres, fully on rear tyres for practice. Some people use 30mm rear tyre to further aid rear traction, but only some cars can use this configuration.
As your race meeting continues, grip usually comes up so I do not apply any further additive, or grip roll may occur.
The tip is to stiffen the front of the car to aid stability and good change of direction. The rear needs to grip.
I hope this helps
