stock SetVehicleSpeed(vehicleid, Float:speed)
{
new Float:x1, Float:y1, Float:z1, Float:x2, Float:y2, Float:z2, Float:a;
GetVehicleVelocity(vehicleid, x1, y1, z1);
GetVehiclePos(vehicleid, x2, y2, z2);
GetVehicleZAngle(vehicleid, a); a = 360 - a;
x1 = (floatsin(a, degrees) * (speed/200) + floatcos(a, degrees) * 0 + x2) - x2;
y1 = (floatcos(a, degrees) * (speed/200) + floatsin(a, degrees) * 0 + y2) - y2;
SetVehicleVelocity(vehicleid, x1, y1, z1);
}
Und wenn ja...
Es ist in mp/h und nicht km/h oder? 
