Did you ever measure the wheelbase from side to side? Back in the '80s we "staggered" the front wheels in my Chevelle drag car to get about an inch and a half more rollout in the starting beams. If you slammed the brakes and weren't ready for it, the car would dart to the right because that front wheel was set back farther than the left. I'd try measuring the centerline from side to side and then get the car in the air and get it "squared". If for nothing else, it might eliminate something else from the equation.