My old pump gas Duster had a 8 3/4 that was bending while I raced and drove it, it would wonder on the street with mix type tires, bias in the front with radials in the back and do the same with radials in the front and bias in the back It wouldn't wonder as much on the street with the same type tires front and back but it would go straight at the tracks with either combination, both 1/8 and 1/4 with mixed type of tires I ended up finding a worn idler arm, it had been replaced when I first assemlbed the car and it had less than 3000 miles total on it whe I replaced it the second time, that straighten all the problems out after that