Stihl MS 661 | 500i | 462 | 461 | 400c The STIHL MS 661 (91.1 cc) is the most powerful and largest, followed by the MS 500i (79.2 cc) and the new MS 400c (62.6 cc), while the MS 462 (72.2 cc) offers a strong power-to-weight ratio, and the MS 461 (77 cc) is the predecessor to the 462. The choice depends on the user's need for extreme power (661), advanced fuel injection and a balance of power (500i), a lighter professional option with advanced M-Tronic (462), or a strong carb-powered workhorse (4