The FIRE is a series of automobile engines from Fiat Powertrain Technologies, built in FCA's Termoli, Betim and also in Dundee, MI plants. It was designed by Italian design firm Rodolfo Bonetto. It is constructed by robot assembly plants ("Robogate") to reduce costs.

In internal combustion engines, a variable-length intake manifold (VLIM),variable intake manifold (VIM), or variable intake system (VIS) is an automobile internal combustion engine manifold technology. As the name implies, VLIM/VIM/VIS can vary the length of the intake tract in order to optimise power and torque across the range of engine speed operation, as well as to help provide better fuel efficiency. This effect is often achieved by having two separate intake ports, each controlled by a valve, that open two different manifolds – one with a short path that operates at full engine load, and another with a significantly longer path that operates at lower load. The first patent issued for a variable length intake manifold was published in 1958, US Patent US2835235 by Daimler Benz AG.