I'm replacing the TCC solenoid due to a P0741 code and I was thinking about installing a High Stall Torque converter while I was at it. Where would I get one? Any suggestions as to what RPM to go with?
A high stall convertor in a base Deville will get you nothing but a car that is murder to drive in traffic. It won't change your redline, it won't change your shift points, it won't change the speed limiter fuel cutoff (base Deville ? Probably 112 mph). The VIN Y engine/3.11 final drive is set up to run efficiently in the low to midrange power curve - it is not designed to be a top end screamer or drag queen.