ASTARPRO Torque Converter GM TH350 Torque Converter for TH-350 and TH-400 Transmissions - 2700-3000 RPM Stall Speed - 10.75 Inch Flexplate Bolt Pattern - 500 Horsepower Maximum ApplicationsPerformance torque converter for street and track use for improved launch and acceleration Made in the USA using high quality materials and assembly. Economically priced for performance on a budget. 2700 3000 RPM stall speed to match your engine and camshaft needs. Ideal torque converter for small block applications up to 500 horsepower without nitrous or super turbochargers. GM TH350 TH40030 Spline 10. 750 in. Bolt Circle. Stall Speed: 2700 3000 RPM.