High speed stability issues

30 by 10 by 15 on 9.5 inch wide wheel Hoosier slicks ,inner tubes 12psi. I have only made 7 runs. Progressively faster. Started to get squirrelly at 124 when I took my foot out of the throttle. Double adjustable Viking shocks all around. Set at there starting recommendations. Havent run the car enough or hard enough to deal with those yet. Cal tracs with there split mono leafs.i am going to go progressively faster for safety sake. Maybe the extra caster will have solved the issue. Just apprehensive and hoping for some guidance. Any thoughts on adjustable strut rods? Worth the money?