1800-2200 RPM Stall Speed Five Star Viskus Drive Torque Converter, High Stall Stator, Negative Impeller, GM 8.1L Gas With Allison LCT-1000. 1800-2200 RPM Stall Speed Five Star Viskus Drive Torque Converter, Factory High Stall Stator, Negative Impeller, GM 8.1L Gas With Allison LCT-1000