The only reason I posted on this thread is because I run similar speeds, have a similar size car with similar tire set up as the original poster - and have had similar wander issues in the past. Trying to compare my issues with some one who has a dedicated race car running in the 140 and above mph range is almost meaningless. My car was never designed ( reads aerodynamic as a box of velveta cheese ) to do what I am asking it to. I think some older cars catch a lot of air under them at speed and this alone creates handling issues. Ride height changes and in old Mopars this often changes alignment specs, aspecially in the camber and toe areas. Pulled the front sway bar off my car earlier this year to try and cut an ugly 40 pounds off the car. Big mistake. Ran in a moderate cross wind and just about saturated my depends. Put it back on. I guess my point is that there is a lot more issues with handling than just tires - although tires obviously play a major roll. Just changing rear tire pressure 5 psi makes a handling difference. Making sure your rear suspension is tight and properly aligned ( to the frame ) is often over looked and Ma Mopar didn't do too good in this area from the factory with old iron.