How to make a plane flying more than 100 studs?

Hey guys!
I wanna make my Plane faster by modify the script. But it doesn't work and always flies normally (100 studs) or does nothing! Please help me with the following script the it flies faster (300-500 studs) are perfect

local seat=script.Parent
local data=seat.Configuration
local owner=nil
local running=false
local x=1
local y=1

seat.ChildAdded:connect(
function(w)
if w.className=="Weld" and w.Name=="SeatWeld" then
local char=w.Part1.Parent
local player=game.Players:FindFirstChild(char.Name)
if player~=nil then
owner=player
seat.ChildRemoved:connect(
function(w2)
if w2==w then
owner=nil
end
end
)
seat.BodyVelocity.maxForce=Vector3.new(10,10,10)*data.MaxForce.Value
seat.BodyGyro.maxTorque=Vector3.new(1,1,1)*1000
local spd=0
local gui=seat.ScreenGui:clone()
gui.Parent=player.PlayerGui
gui.Frame.Faster.MouseButton1Click:connect(
function()
spd=math.min(spd+data.MaxSpeed.Value/10,data.MaxSpeed.Value)
gui.Frame.Speed.Text=math.floor(spd)
end
)
gui.Frame.Slower.MouseButton1Click:connect(
function()
spd=math.max(spd-data.MaxSpeed.Value/10,0)
gui.Frame.Speed.Text=math.floor(spd)
end
)
while owner==player do
seat.BodyVelocity.velocity=seat.CFrame.lookVector*spd
wait()
end
gui:remove()
seat.BodyVelocity.velocity=Vector3.new(0,0,0)
seat.BodyVelocity.maxForce=Vector3.new(0,0,0)
seat.BodyGyro.maxTorque=Vector3.new(0,0,0)
end
end
end
)

seat.Changed:connect(
function()
if not running then
local cur=seat.Steer
local cur2=seat.Throttle
running=true
while (cur~=10 or cur2~=10) do
y=y-seat.Steer*data.TurnSpeed.Value
x=x-seat.Throttle*data.TurnSpeed.Value
seat.BodyGyro.cframe=CFrame.new(0,0,0)*CFrame.Angles(0,math.rad(y),0)*CFrame.Angles(math.rad(x),0,0)
wait()
end
running=false
end
end
)