These motors are the big power producers used in 1/8th scale offroad and oval cars. All the motor variants are 42mm in diameter (including the outside cooling fins) and 68mm long with a 5mm shaft to drive these big cars.
The 1950KV motors are designed for slick to medium track surfaces for 1/8 Scale offroad eBuggy. On higher bite or large 1/8th scale offroad tracks, the 2250KV is the motor to have for eBuggy.
On 1/8th scale oval tracks, start with the 2250KV motor when the track is medium sized and/or medium traction surface. The 2650KV motor is a great power plant on large or high traction surfaces, especially in Late Model.
All the motors have zero, fixed timing. For initial setup, add 15 degrees in your ESC, and watch your temperatures (do not exceed 160 degrees F).