Use:
function getElementSpeed ( element , unit )
if not element or not isElement ( element ) then
return false
end
if unit == "kph" then
unit = 1.61
else
unit = 1
end
local velX , velY , velZ = getElementVelocity ( element )
return ( velX ^ 2 + velY ^ 2 + velZ ^ 2 ) ^ 0.5 * unit * 100
end
function setElementSpeed ( element , unit , speed )
if not element or not isElement ( element ) then
return false
end
if not speed then
speed = 0
end
local acSpeed = getElementSpeed ( element , unit )
local diff = speed / acSpeed
local velX , velY , velZ = getElementVelocity ( element )
setElementVelocity ( element , velX * diff , velY * diff , velZ * diff )
return true
end