You might want to adjust the caster. Formula Fords tend to have between 3-5 degrees of caster angle... Yours only has 0.5 deg, hence it tries to behave acting like a shopping cart wheel as soon as force is applied... I raised caster towards 5 degrees and then it handles as I would expect.
Just adjust the 'WBTYRE_TOP and WBTYRE_BOTTOM of the front rack in the respective front/ rear movement, e:g:
WBTYRE_TOP=0.077087, 0.109425, -0.00998
WBTYRE_BOTTOM=0.053974, -0.127954, 0.00998
(adjusting last numbers = Caster; mechanical trail, largely affects the amount of FFB)
(adjusting first numbers = KPI (King Pin / Steering inclination (affects amount of scrub, can be further tuned with the RIM_OFFSET) (the car has too much scrub, open wheelers with small tires tend to have between 5-20mm scrub radius max)
KPI and Caster always go hand in hand, as the wheel movements describe arcs, see the vid below for proper explanation:
Very good explaination of basics of suspension kinematics here:
You also might want to look into the Formula Vee, as the roll centers try to reach the moon. (play with the angles of the wishbones to adjust): (See attached image).