A-Chassis vehicle changing direction while accelerating

  1. What do you want to achieve?
    I want to make vehicle accelerate normally without it changing direction

  2. What is the issue?
    Vehicle is slowly changing direction when i accelerate

  3. What solutions have you tried so far?
    Turned player and every single part inside vehicle massless, Searched for solution in developer forum, Messed with custom physical properties of wheel (i don’t know much about this properties)

Video:

A-Chassis version is 6.52S2

Script here:

--[[
		___      _______                _     
	   / _ |____/ ___/ /  ___ ____ ___ (_)__ 
	  / __ /___/ /__/ _ \/ _ `(_-<(_-</ (_-<
	 /_/ |_|   \___/_//_/\_,_/___/___/_/___/
 						SecondLogic @ Inspare
]]

local Tune = {}

--[[Misc]]
	Tune.LoadDelay		= .1		-- Delay before initializing chassis (in seconds)
	Tune.AutoStart		= true		-- Set to false if using manual ignition plugin
	Tune.AutoFlip		= true		-- Set to false if using manual flip plugin
	
--[[Wheel Alignment]]
	--[Don't physically apply alignment to wheels]
	--[Values are in degrees]
	Tune.FCamber		= -1
	Tune.RCamber		= -1
	Tune.FToe			= 0
	Tune.RToe			= 0
	
--[[Weight and CG]]
	Tune.Weight			= 4122		-- Total weight (in pounds)
	Tune.WeightBSize	= {			-- Size of weight brick (dimmensions in studs ; larger = more stable)
	 --[[Width]]		7.03,
	 --[[Height]]		5.35,
	 --[[Length]]		18.11	}
	Tune.WeightDist		= 50		-- Weight distribution (0 - on rear wheels, 100 - on front wheels, can be <0 or >100)
	Tune.CGHeight		= .8		-- Center of gravity height (studs relative to median of all wheels)
	Tune.WBVisible		= false		-- Makes the weight brick visible
	
	--Unsprung Weight
	Tune.FWheelDensity	= .1		-- Front Wheel Density
	Tune.RWheelDensity	= .1		-- Rear Wheel Density
	Tune.FWLgcyDensity	= 1			-- Front Wheel Density [PGS OFF]
	Tune.RWLgcyDensity	= 1			-- Rear Wheel Density [PGS OFF]
	
	Tune.AxleSize		= 2			-- Size of structural members (larger = more stable/carry more weight)
	Tune.AxleDensity	= .1		-- Density of structural members
	
--[[Susupension]]
	Tune.SusEnabled		= true		-- works only in with PGSPhysicsSolverEnabled, defaults to false when PGS is disabled
	
	--Front Suspension
	Tune.FSusDamping	= 500		-- Spring Dampening
	Tune.FSusStiffness	= 9000		-- Spring Force
	Tune.FAntiRoll 		= 50		-- Anti-Roll (Gyro Dampening)
	
	Tune.FSusLength		= 2			-- Suspension length (in studs)
	Tune.FPreCompress	= .3		-- Pre-compression adds resting length force
	Tune.FExtensionLim	= .3		-- Max Extension Travel (in studs)
	Tune.FCompressLim	= .1		-- Max Compression Travel (in studs)
	Tune.FSusAngle		= 80		-- Suspension Angle (degrees from horizontal)
		
	Tune.FWsBoneLen		= 5			-- Wishbone Length
	Tune.FWsBoneAngle	= 0			-- Wishbone angle (degrees from horizontal)
	Tune.FAnchorOffset	= {			-- Suspension anchor point offset (relative to center of wheel)
	 --[[Lateral]]		-.4		,	-- positive = outward
	 --[[Vertical]]		-.5		,	-- positive = upward
	 --[[Forward]]		0		}	-- positive = forward
	
	--Rear Suspension
	Tune.RSusDamping	= 500		-- Spring Dampening
	Tune.RSusStiffness	= 9000		-- Spring Force
	Tune.RAntiRoll 		= 50		-- Anti-Roll (Gyro Dampening)

	Tune.RSusLength		= 2			-- Suspension length (in studs)
	Tune.RPreCompress	= .3		-- Pre-compression adds resting length force
	Tune.RExtensionLim	= .3		-- Max Extension Travel (in studs)
	Tune.RCompressLim	= .1		-- Max Compression Travel (in studs)
	Tune.RSusAngle		= 80		-- Suspension Angle (degrees from horizontal)
		
	Tune.RWsBoneLen		= 5			-- Wishbone Length
	Tune.RWsBoneAngle	= 0			-- Wishbone angle (degrees from horizontal)
	Tune.RAnchorOffset	= {			-- Suspension anchor point offset (relative to center of wheel)
	 --[[Lateral]]		-.4		,	-- positive = outward
	 --[[Vertical]]		-.5		,	-- positive = upward
	 --[[Forward]]		0		}	-- positive = forward

	--Aesthetics	
	Tune.SusVisible		= true			-- Spring Visible
	Tune.WsBVisible		= false			-- Wishbone Visible
	Tune.SusRadius		= .2			-- Suspension Coil Radius
	Tune.SusThickness	= .1			-- Suspension Coil Thickness
	Tune.SusColor		= "Bright red"	-- Suspension Color [BrickColor]
	Tune.SusCoilCount	= 6				-- Suspension Coil Count
	Tune.WsColor		= "Black"		-- Wishbone Color [BrickColor]
	Tune.WsThickness	= .1			-- Wishbone Rod Thickness
	
--[[Wheel Stabilizer Gyro]]
	Tune.FGyroDamp		= 100		-- Front Wheel Non-Axial Dampening
	Tune.RGyroDamp		= 100		-- Rear Wheel Non-Axial Dampening
	
--[[Steering]]
	Tune.SteerInner		= 36		-- Inner wheel steering angle (in degrees)
	Tune.SteerOuter		= 37		-- Outer wheel steering angle (in degrees)
	Tune.SteerSpeed		= .05		-- Steering increment per tick (in degrees)
	Tune.ReturnSpeed	= .1		-- Steering increment per tick (in degrees)
	Tune.SteerDecay		= 320		-- Speed of gradient cutoff (in SPS)
	Tune.MinSteer		= 10		-- Minimum steering at max steer decay (in percent)
	Tune.MSteerExp		= 1			-- Mouse steering exponential degree
	
	--Steer Gyro Tuning
	Tune.SteerD			= 1000		-- Steering Dampening
	Tune.SteerMaxTorque	= 50000		-- Steering Force
	Tune.SteerP			= 100000	-- Steering Aggressiveness
	
--[[Engine]]
	--Torque Curve
	Tune.Horsepower		= 390		--	[TORQUE CURVE VISUAL]
	Tune.IdleRPM		= 950		--		https://www.desmos.com/calculator/2uo3hqwdhf
	Tune.PeakRPM		= 5750		--		Use sliders to manipulate values
	Tune.Redline		= 6000		--		Copy and paste slider values into the respective tune values
	Tune.EqPoint		= 5252
	Tune.PeakSharpness	= 20
	Tune.CurveMult		= .5
	
	--Incline Compensation
	Tune.InclineComp	= 1.7			-- Torque compensation multiplier for inclines (applies gradient from 0-90 degrees)
	
	--Misc
	Tune.RevAccel		= 150		-- RPM acceleration when clutch is off
	Tune.RevDecay		= 75		-- RPM decay when clutch is off
	Tune.RevBounce		= 500		-- RPM kickback from redline
	Tune.IdleThrottle	= 3			-- Percent throttle at idle
	Tune.ClutchTol		= 500		-- Clutch engagement threshold (higher = faster response)
	
--[[Drivetrain]]	
	Tune.Config			= "AWD"		--"FWD" , "RWD" , "AWD"
	
	--Differential Settings	
	Tune.FDiffSlipThres	= 50		-- 1 - 100%				(Max threshold of applying full lock determined by deviation from avg speed)
	Tune.FDiffLockThres	= 50		-- 0 - 100%				(0 - Bias toward slower wheel, 100 - Bias toward faster wheel)
	Tune.RDiffSlipThres	= 50		-- 1 - 100%
	Tune.RDiffLockThres	= 50		-- 0 - 100%
	Tune.CDiffSlipThres	= 50		-- 1 - 100%				[AWD Only]
	Tune.CDiffLockThres	= 50		-- 0 - 100%				[AWD Only]
	
	--Traction Control Settings
	Tune.TCSEnabled		= true		-- Implements TCS
	Tune.TCSThreshold	= 20		-- Slip speed allowed before TCS starts working (in SPS)
	Tune.TCSGradient	= 20		-- Slip speed gradient between 0 to max reduction (in SPS)
	Tune.TCSLimit		= 10		-- Minimum amount of torque at max reduction (in percent)
	
--[[Transmission]]
	Tune.TransModes		= {"Auto"}								--[[
	[Modes]
		"Auto"		: Automatic shifting
		"Semi"		: Clutchless manual shifting, dual clutch transmission
		"Manual"	: Manual shifting with clutch
		
		>Include within brackets
			eg: {"Semi"} or {"Auto", "Manual"}								
		>First mode is default mode													]]
	
	--Automatic Settings
	Tune.AutoShiftMode	= "Speed"												--[[
	[Modes]
		"Speed"		: Shifts based on wheel speed
		"RPM"		: Shifts based on RPM											]]	
	Tune.AutoUpThresh	= -200		--Automatic upshift point 	(relative to peak RPM, positive = Over-rev)
	Tune.AutoDownThresh = 1400		--Automatic downshift point (relative to peak RPM, positive = Under-rev)
	
	--Gear Ratios
	Tune.FinalDrive		= 4.06			-- Gearing determines top speed and wheel torque
	Tune.Ratios			= {				-- Higher ratio = more torque, Lower ratio = higher top speed
		--[[Reverse]]	3.70		,	-- Copy and paste a ratio to add a gear
		--[[Neutral]]	0			,	-- Ratios can also be deleted
		--[[ 1 ]]		3.53		,	-- Reverse, Neutral, and 1st gear are required
		--[[ 2 ]]		2.04		,
		--[[ 3 ]]		1.38		,
		--[[ 4 ]]		1.03		,
		--[[ 5 ]]		0.81		,
		--[[ 6 ]]		0.64		,
	}
	Tune.FDMult			= 1.5			-- Ratio multiplier (Change this value instead of FinalDrive if car is struggling with torque ; Default = 1)
	
--[[Brakes]]
	Tune.ABSEnabled		= true		-- Implements ABS
	Tune.ABSThreshold	= 20		-- Slip speed allowed before ABS starts working (in SPS) 

	Tune.FBrakeForce	= 1500		-- Front brake force
	Tune.RBrakeForce	= 1000		-- Rear brake force
	Tune.PBrakeForce	= 5000		-- Handbrake force
	
	Tune.FLgcyBForce	= 15000		-- Front brake force [PGS OFF]
	Tune.RLgcyBForce	= 10000		-- Rear brake force [PGS OFF]
	Tune.LgcyPBForce	= 25000		-- Handbrake force [PGS OFF]
	
--[[[Default Controls]]
	--Peripheral Deadzones
	Tune.Peripherals = {
		MSteerWidth				= 67		,	-- Mouse steering control width	(0 - 100% of screen width)
		MSteerDZone				= 10		,	-- Mouse steering deadzone (0 - 100%)
		
		ControlLDZone			= 5			,	-- Controller steering L-deadzone (0 - 100%)
		ControlRDZone			= 5			,	-- Controller steering R-deadzone (0 - 100%)
	}
	
	--Control Mapping
	Tune.Controls = {
		
	--Keyboard Controls
		--Mode Toggles
		ToggleTCS				= Enum.KeyCode.T					,
		ToggleABS				= Enum.KeyCode.Y					,
		ToggleTransMode			= Enum.KeyCode.M					,
		ToggleMouseDrive		= Enum.KeyCode.R					,
		
		--Primary Controls
		Throttle				= Enum.KeyCode.Up					,
		Brake					= Enum.KeyCode.Down					,
		SteerLeft				= Enum.KeyCode.Left					,
		SteerRight				= Enum.KeyCode.Right				,
		
		--Secondary Controls
		Throttle2				= Enum.KeyCode.W					,
		Brake2					= Enum.KeyCode.S					,
		SteerLeft2				= Enum.KeyCode.A					,
		SteerRight2				= Enum.KeyCode.D					,
		
		--Manual Transmission
		ShiftUp					= Enum.KeyCode.E					,
		ShiftDown				= Enum.KeyCode.Q					,
		Clutch					= Enum.KeyCode.LeftShift			,
		
		--Handbrake
		PBrake					= Enum.KeyCode.P					,
		
	--Mouse Controls
		MouseThrottle			= Enum.UserInputType.MouseButton1	,
		MouseBrake				= Enum.UserInputType.MouseButton2	,
		MouseClutch				= Enum.KeyCode.W					,
		MouseShiftUp			= Enum.KeyCode.E					,
		MouseShiftDown			= Enum.KeyCode.Q					,
		MousePBrake				= Enum.KeyCode.LeftShift			,
		
	--Controller Mapping
		ContlrThrottle			= Enum.KeyCode.ButtonR2				,
		ContlrBrake				= Enum.KeyCode.ButtonL2				,
		ContlrSteer				= Enum.KeyCode.Thumbstick1			,
		ContlrShiftUp			= Enum.KeyCode.ButtonY				,
		ContlrShiftDown			= Enum.KeyCode.ButtonX				,
		ContlrClutch			= Enum.KeyCode.ButtonR1				,
		ContlrPBrake			= Enum.KeyCode.ButtonL1				,
		ContlrToggleTMode		= Enum.KeyCode.DPadUp				,
		ContlrToggleTCS			= Enum.KeyCode.DPadDown				,
		ContlrToggleABS			= Enum.KeyCode.DPadRight			,
	}
	
--[[Weight Scaling]]
	--[Cubic stud : pounds ratio]
	--[STANDARDIZED: Don't touch unless needed]
	Tune.WeightScaling = 1/50	--Default = 1/50 (1 cubic stud = 50 lbs)
	Tune.LegacyScaling = 1/10	--Default = 1/10 (1 cubic stud = 10 lbs) [PGS OFF]
	
return Tune

Set all the things under wheel alignment to 0

1 Like

i set thing under wheel alignment to 0, still not worked :face_with_diagonal_mouth:

1 Like

Is the car supposed to be realistic?

1 Like

nope!, since am not make my game as drive game.

Is it a free model? (Sorry about the questions just trying to narrow it down.)

1 Like

yes, i just only changed the a-chassis version.

The person that made it may have wanted it to be realistic. Realism would be so that it would start kind of turning even if you did nothing. So if you want a no turning straight drive, you might have to make a new one.

1 Like