Suspension - Inboard Suspension

Overview 

Inboard suspension is a configuration where the shock is not directly connected to the control arms or uprights. Instead a pushrod connects the lower control arm to a rocker which then rotates to compress the shock. 

There are a number of different ways to configure the shock position with inboard suspension: 

Advantages

There are a number of benefits to having inboard suspension, making it a very popular choice for F1 and other race cars:

• It is easier to get access to the shocks to tune the suspension stiffness if they are not blocked by the wheels (this assumes you can remove panels from the vehicle)
• It is much easier to control the load paths as forces "flow" through the space frame. As seen above there are a number of different configurations possible; thus allowing the flexibility to design from maximum torsional stiffness. 
• The addition of the pushrod/rocker geometry allows the wheel travel to be decoupled from he suspension travel. For example, a desert trucks can get 48" of wheel travel with 24" or less shocks, while Formula cars use 6" travel shocks to get 2" at the wheel. 
• Inboard shocks can be more aerodynamic
  

Disadvantages 

• Slightly more complicated (more moving parts)
• Possibly a slightly higher centre of gravity