An aneriod is a fuel to air ratio device that limits the amount of fuel rack travel untill there is proper boost. In other words, if you step on the throttle without this device on the IP,you would get alot of black smoke untill the turbo "spools up" and pumps in enough air to match the amount of fuel being dumped in.

Also if these leak air or are not adjusted properly they can cause performance complaints.

__________________
87' 300sdl