I am not a big fan of Strange shocks. I have them on my dragster and don't like them too much. With that car knocking on the 7's I'd invest in the best you can afford, Santhuff would be a great choice. Spring choice will also be critical I prefer Eibach over all others. Video of the rear tire and suspension should reveal alot. FWIW I ran 6.5psi in the Dart which was similiar weight and et.