car sinks...
 

so my brother has a 98 z28 wit 108xxx. runs fine and accelerates great but when its cold and you put it in gear (auto) such as reverse, the car kinda sinks (like twists) towards the driver side

maybe a trans/trq arm mount???

i would check the motor mounts. if the driver side is worn out enough, it would probably sink that way.

definitely check the trans mount too. usually on WOT 1-2 shifts it bangs or the shifter moves alot. just looking at it, you can't tell they are bad. support the trans, remove the crossmember and mount, and see if its bad. i would get a spohn poly to replace it.

i would be curious as to whether or not a strut is bad on the driveside. for it to only do it while cold is a little odd.