eventually,i wanna put some h.i.d fogs to replace wht i use now. im goin with a pair of projectors for it but not sure how i will get power to them. is tht wht a relay is used for?

everything is pretty much stock,im runnin kyb gr2's in the rear,short ram intake soon.
Audio:Kenwood Head Unit-200watts,bluetooth,direct ipod control
6.5 inch 190 watt Sony on the rear deck + two 300 wattPyramid tw28 bullet tweeters also on deck
lightning audio 750 watt 10inch sub + 750 watt lightning audio amp
one mini nitro bmw 300 watt 4 channel amp pushing my highs and mids
bought the car with 79,xxx miles few months ago.
one problem tht i cant figure out is my steering..if im on a bumpy road and im braking i have to fight to keep it straight. it feels like the wheels wanna go two different directions..an ideas why?