When Chrysler and Fiat became partners, one of the underlying reasons for the deal was that Chrysler would get to use Fiat’s so-called “MultiAir” valve-control engine technology. Chrysler executives are quoted as saying that alone will be worth a minimum of $10 billion to the Chrysler line. Fiat claims that MultiAir technology improves mileage by at least 10% while reducing carbon emissions by 10%. In addition, the technology provides 15% more torque.
In a standard internal combustion gasoline engine, the valves that allow air into the cylinders open all the way no matter how fast the car is moving. In other words, the same phenomena occurs while driving 100 mph or just coasting. This conventional “pumping process” wastes gas. The MultiAir system, developed by Fiat engineer Rinaldo Rinolfi at a reported cost of $100 million, employs an electronically-controlled hydraulic valve-lifter system that automatically adjusts the amount and duration of air allowed into the cylinder chambers.
An Electronic Control Unit (ECU) monitors the engine’s RPMs. In turn, the ECU drives a solenoid that opens and closes the valves. The action gets more power from the fuel, thereby increasing efficiency.
There are other car manufacturers employing similar technologies, most notably BMW, with its “Valvetronic” system. However, the Fiat technology is able to control each cylinder individually, while BMW’s works all valves together equally. Further, the Fiat version easily adapts to almost any existing engine. The primary component, called “The Brick”, is a block with pistons , passages and valves, that simply bolts on top of an existing head.
The first car to get MultiAir is the Fiat 500, now made by and sold in a US-modified version by Chrysler. It uses a 1.4-liter turbo four-cylinder engine rated at 30 mpg city and 38 mpg highway. Edmunds says the engine is “smooth”, but that mileage isn’t so great with automatic transmission and recommends the engine with stick shift. You can buy these engines remanufactured at http://www.remanufacturedenginesforsale.com/remanufactured-engines/remanufactured-chrysler-engines-sale/. They seem to have the most reasonable prices online for Chrysler engines…at least remanufactured Chrysler engines. Buying used can be a little scary, especially on the internet.
Some Chrysler/Fiat 500 owners have reported that they can get better than 50 mpg by driving at the speed limit, accelerating slowly and avoiding revving in the lower gears. However, most users report averaging 32-36 mpg under normal use.
