The Chassis designer is the baseline for any car model and all its subsequent trims. This is where the car's main purpose and the range of targeted demographics are determined, using different combinations of chassis and panel materials, chassis types, engine layouts, and suspension designs, which, of course, depend on the year of the design. Once you select the car type (by selecting a body style or family of related body styles), you can begin.
Panel Material[edit | edit source]
The first option you are given is panel material. Panels are the series of shaped plates that act like the outer skin of the car. They affect safety and weight. Availability of these materials and manufacturing flags (such as Limited Production or No Mass Production) is dependent on the year of the model. The materials may also require certain equipment in your factories such as various machine presses. Those materials are (in order of availability):
- Steel: Raw untreated steel, cheapest material. These require a small factory and steel presses.
- Treated Steel: Raw steel is passed through a series of chemical baths to build up resistance to corrosion without using Zinc galvanization. Requires a large factory and steel presses.
- Corrosion Resistant Steel: Steel alloy designed for corrosion resistance, built with additional environmental protections such as tighter seals and bushings. Requires small factory and steel presses.
- Fiber Glass: woven glass fibers encased in a plastic-like resin/epoxy coat. Cheap, easy to work with, very light, very unsafe and uncomfortable (due to lack of sound muffling). Limited production. SMC injection (compression molding) is suggested but not required.
- Aluminium: Choice material for modern cars. This metal is lighter and naturally corrosion resistant compared to steel (in real life, Aluminium does rust but its oxide, called Corundum, is transparent and tougher than Aluminium itself) however this material is also somewhat more expensive and harder to work with. Limited production until the '90s. Aluminium presses suggested.
- Partial Aluminium: Most body panels are built out of steel. However the trunk and hood are built out of Aluminium. A good compromise choice. Steel presses and small factory required.
- Carbon Fiber: Carbon fiber is a material made of thin carbon fibers woven into a very strong and very lightweight material, which is then encased in epoxy. Commonly used in the construction of super/hyper cars. However it is very expensive. Limited Production. Requires small factory. Carbon plant suggested.
Chassis Type[edit | edit source]
The chassis of the car serves as the backbone of the entire car. This option is critical in determining how your car will be built and what purposes it can fulfill
- Ladder Frame: Also known as body-on-frame, this design dates back to the horse and buggy. Very simple and cheap to build, these frames are very durable and easy to repair. The car's body is built seperately, and then mated onto the frame. Ladder frames are heavy and negatively impact safety. Ladder frames are most commonly used on utility and offroad vehicles (such as panel vans, pickup trucks, and earlier SUVs). One of the most famous American taxi and police cars, the Ford Crown Victoria, used a body-on-frame construction method. Ladder frames are incompatible with mid and rear engined layouts.
- Monocoque: Also known as Unibody, this design was exclusive to higher end cars in the mid 20th century, however as technology advanced, it trickled down towards the common passenger cars in the 60s and 70s, especially among smaller cars. It became very common in the 80's, and by the 90's became the standard for passenger vehicles. This method keeps the car's body and "frame" together as one 'shell' (hence the name Mono-coque, mono = one, coque = French for shell). This construction method is very safe, average weight, but is more complicated in design and construction.
- Space Frame: This method works just like the ladder frame, a body is built on top of a frame. However this method is not used for utility vehicles due to it unfit for mass production. This construction method was used in low volume sports car production of the 40's and 50's. The car remains lightweight due to the tubular design of the frame rather than thick heavy duty steel rails. No mass production
- Semi-Space Frame: A compromise between the space frame and monocoque designs. Small space-frame subframes are used under the trunk and engine compartements, and attached to a smaller monocoque that covers the passenger area. This is used in higher end sports cars and super cars.
- Light Truck Monocoque: The front "cabin" end of the truck is built monocoque style, and the rear "bed" of the truck is placed on top of a frame. This is a compromise between monocoque and ladder designs. An example of this design is the Honda Ridgeline, a midsize truck.
Comparison between a body-on-frame chassis (left) and a unibody chassis (right)
Chassis Material[edit | edit source]
The material of the chassis helps in determining the cost, weight and structural integrity of the car. The design of the chassis affects what materials are available
- Steel: Raw untreated steel, cheapest material. Requires a small factory and steel presses.
- Galvanized Steel: Steel that has gone through a Zinc galvinization process in order to build up corrosion resistance. Requires medium factory and galvanization plant.
- Corrosion Resistant Steel: Steel alloy designed for corrosion resistance, built with additional environmental protections such as tighter seals and bushings. Requires small factory and steel presses
- Advanced High Strength Steel: Modern steel alloys designed to be lighter and tougher than traditional steel. Requires a small factory and steel presses.
- Light AHS Steel: Using the same material, however with additional weight saving techniques by removing additional metal in the chassis. Results in lighter but weaker chassis compared to normal AHS steel. Requires a small factory and steel presses. Unavailable for ladder chassis or space frame.
- Glued Aluminium: Strong and light aluminium, held together with powerful adhesive. Requires small factory. Limited production. The only available choice for a semi-space frame chassis
- Carbon Fiber: Very strong and lightweight material. The carbon fiber is shaped in a tub form. Limited production. Requires small factory and carbon plant. Monocoque only
Engine Placement[edit | edit source]
This option will determine the availability of drive types (FWD, RWD, AWD, 4x4) and weight distribution
- Front Longitudinal: The most basic and earliest engine/drivertrain layout. Allows for FWD, RWD, AWD and 4x4. The engine is positioned in front, parralel to the direction of the car, and puts power through a driveshaft (except for Longitudinal FWD). Most sports/luxury cars, utility vehicles and pre-80's passenger cars used L.RWD setup. Longitudinal FWD is rare as it is disadvantegous compared to Transverse FWD. Longitudinal AWD is common as a higher level offering from a more basic RWD platform. 4x4 is only available on front longitudinal setups, and is common in offroad and utility vehicles. Cars that use L.RWD include American sports cars and utility vehicles, almost all BMW models, and many japanese RWD sports cars of the 90's. Cars that use L.FWD include the 70's Cadillac Eldorado. Cars that use L.AWD include the Subaru Impreza. Cars that use L.4x4 include offroad/utility vehicles like the Ford F-Series, Dodge Ram, and Chevrolet Silverado/GMC Sierra.
- Front Transverse: Engine layout of choice for modern FWD and AWD passenger cars. Allows for FWD and AWD. The engine is positioned in front, perpendicular to the direction of the car, and puts power through a transaxle to the front wheels and an additional driveshaft for the rear wheels in AWD. Most passenger cars post 80's use the T.FWD setup, larger crossovers and modern SUV's may use T.AWD. This setup is popular among basic, economical cars meant for the average commuter and family. Cars that use T.FWD include the Honda Civic. Cars that use T.AWD include the Mitsubishi Lancer Evolution.
- Mid Longitudinal: Engine layout used in high end sports cars. Gives the best weight balance, closest to 50/50, however is isn't as spacious as other setups. Allows for RWD and AWD. Examples include the Honda/Acura NSX (Mid.L.RWD)
- Mid Transverse: Engine layout used in all kinds of sports cars. Gives the best weight balance, closest to 50/50, however is isn't as spacious as other setups. Allows for RWD and AWD. Examples include the Toyota MR2 (Mid.T.RWD) or the Lamborghini Miura.
- Rear Longitudinal: Engine layout used in sports cars. Allows for RWD and AWD. Examples include the Porsche 911 (Rear.L.RWD)
Suspension Setup[edit | edit source]
Suspension choices will affect handling, production and engineering costs, and available drive types. Suspension choice in turn is affected by chassis type and engine placement.
Solid axles are the most basic suspension setup. The wheels are interconnected by a solid metal beam. This solid metal beam contains half-shafts within it which connects the wheels to the drivetrain (if the axle is powered). The drivetrain is part of the axle assembly, which aids in the simplicity of a solid axle. In Automation solid axles come with two choices for spring type - leaf springs or coil springs. Leaf springs are the most basic suspension design, in which a semi-elliptical metal spring carries the load. The metal spring works by flexing upwards in response to load shifts. In a coil spring setup, the metal springs are replaced with a coil spring, as seen in all other suspension design. The coil spring is superior to the leaf spring in all metrics except sheer carrying capacity and simplicity. Solid axles in general are good for load bearing and off road use, leaf springs tend to be better for loads and coil springs better for off road. Solid axles are still used on utility and off road vehicles. Heavy duty utility vehicles use leaf springs for its additional load bearing. Older passenger and cheaper sports cars tended to use front independent suspension and solid rear axles with leaf and coil springs, for example many U.S. muscle and pony cars such as the first generations of the Ford Mustang, Pontiac GTO, Plymouth Barracuda. Even the S197 generation Mustang (2004 to 2014) used a rear solid axle with coil springs. It wasn't just these straight line performance cars that used such a setup, even cars better known for their handling prowess such as the Toyota AE86 Corolla Levin/Sprinter Trueno used a solid rear axle. Solid axles can be mounted front or rear, and are available on all chassis designs. Engine position affects suspension design availability. Solid axles cannot be used in the rear if the car is mid or rear engined.
Independent suspension has become the standard for modern passenger cars, and for the front suspension of utility vehicles, aside from commercial vehicles. In Automation there is a diverse selection of independent suspension types. The availability of certain setups depend on chassis type and engine placement, and may affect drive train choice.
- Double Wishbone (Front and Rear)
- Double wishbone uses two wishbone shaped components place on top of one another. This setup is the first available independent suspension setup in game. Double wishbone has decent comfort and good handling. It is popular on mid-range sports cars and luxury cars, such as modern BMW's, Chevrolet SS sedan or Subaru WRX's. Double wishbones can be mounted either front or rear, and is available with all chassis type and engine placements.
- McPherson Strut (Front and Rear)
- McPherson struts use one triangular link and coil spring strut above. This setup is very simple compared to double wishbone, while still providing adequate handling and decent comfort. This setup takes very little horizontal space from the engine bay. It is popular on the majority of normal mass market cars and light trucks. This design cannot be mounted on cars with ladder chassis. In mid and rear engine setup, this suspension can be placed in the rear.
- Torsion Beam (Rear)
- Torsion beams, or Twist-beam use an H-shaped torsion beam. This is the simplest independent suspension setup, mounted in the rear. It is popular with budget economical cars. This design cannot be mounted on cars with a longitudinal engine setup. In mid and rear engine setups this option cannot be used. AWD is not compatible with torsion beam setups. The only allowed engine and drive train setup is Transverse FWD
- Semi Trailing Arm (Rear)
- Semi trailing arm is considered semi-independent suspension. It is a little more complex rear suspension than torsion beam but allows for RWD and AWD. It uses one trailing arm and a transverse beam in between the wheels. This design is popular with budget economical cars that allow for optional AWD. This option cannot be used on mid/rear engine cars.
- Multi-Link (Rear)
- Multi-link suspension suspension is a more complex rear suspension setup. It uses 5-links, two transverse links between the wheels and three lateral links within the setup. This design is fairly comfortable and handles well. It is common among higher end sports cars, such as BMW sedans. This option cannot be used on mid/rear engine cars.
- Pushrod (Rear and Front)
- Pushrod suspension uses multiple rods that push and pull each other. The design is decently comfortable but the best for handling. It is common among super cars, and is the suspension set up choice for Formula 1 race cars. This suspension set up takes up too much space in between the wheels, which means it cannot be installed next to the engine. In front engine setups it is only available in the rear, in rear engine setups it is only available in the front. Mid engine setups allow pushrod suspension to be installed front and rear.