My '77 shop manual states that the same 12" converter is used with both the 302 and the 300 straight 6. With the 302 the stall is 1350-1630 RPM. With the 300 the stall is 1490-1760. Hughes say's the 300 has a higher stall speed because the 300 has better low end torque. The even higher low end torque from my 351w would bring the stock converter closer to 1800 RPM. The high stall speed converters have more friction loss and produce more heat. I don't want either. A cam that moves the torque curve higher, has less low end torque so a high stall speed is needed. My engine was built with low end torque as my goal, so even at 1000 RPM, I have plenty. If I thought I needed more power, I would stroke it. High RPM HP is for racing. Trucks work better with a low and wide torque curve. Again my concern is with the quality of Hughes converters. If the fuel miser has a stall speed of 1200 RPM, as they claim, it should work for me.