thats the first thing an accident investigator looks for, cut springs
what you've actually done is made your car ride in bump steer, which means your getting worse performance than you would with the standard springs, the reason ppl get pissed at f#cktarts who do this is because its dangerous not only for you, but for the ppl who drive around you... i had a friend in hosital becuase a pimply 17yo cut his springs, ran into my mate at 100kph because the car wouldnt handle, he was on life support for 3 weeks, and another 8 months learning how to walk with steel rods in back
get it lowered properly, or get the O.E springs back on!