Steering problem in '88 shelby z

[shelbyzed]

Hi, i've got this problem with the steering and i was wondering if anyone had any suggestions. I've had an alignment done recently, replaced worn passenger steering knuckle and lower ball joint, and the steering rack's tight. When im driving and reach any sort of power, most nocticeably this happens under around half throttle application reachign 3000ish rpm, the car will go from steering perfect straight, and it lurches over, with the steering wheel ending up about 30degrees west of north, and the car still moving in a straight line. If you let off the throttle at this point the car will "lurch" back to having the wheel centred again driving perfectly straight. We've checked the motor mounts thinking that would be a good guess, but they're fine. If anyone has any idea at all on what this could be, i'd be very grateful for the help. The car is drivable like this, but its difficult when driving hard, and letting off between shifts and having the car "lurch" around on me. Please help!
thanks

[The Dude]

Torque steer?

Sounds pretty severe if it is. Is your motor/tranny centered?

[NAJ]

Was the problem there before the alignment?
On any vehicle it is actually the rear wheels that steer the vehicle in the correct direction. On a FWD vehicle there is no large heavy differential in the back to keep things squared up. On FWD the rear wheels must be aligned(Camber and Toe) before aligning the front wheels. Also the vehicle has to be aligned by "thrust angle" not "center line".
When our cars are under acceleration the rear end squats due to engine torque and weight transfer, be sure the rear springs, shocks and sway bar are in proper condition, if the car squats unequally there will be handling problems.
Also be sure your engine mounts are not worn/cracked/broken or engine torque will not be straight back and extra load will be placed on one drive axle or the other.

[shelbyzed]

it's not torque steer, i know what that feels like lol. and i believe the motor and tranny are centered, and the motor mounts are fine, ive checked them. checking the rear is something i have not thought of doing haha. thanks

[shelby_nut]

Check your rack bolts...had the same problem in my 87 SL..steering wheel would be centred one day, off the next, rack bolts were loose and rack was shifting around...