how to find out the stall of a converter??????????????pic included

Be careful about lumping all converters together by a particular size. One company's 10" might go 3K and another might go 5K. Especially with the 10" diameter converters. Those are one of the widest ranged size converters there is. You can find them as low as 2500 and as high as 5500. There's only one way to know for sure. See above.