An e-mail from Elio Motors said the three-cylinder engine’s cooling system is the product of “significant analysis and design.”
The water jacket received a lot of attention, according to Elio. If you don’t know what that is, here’s a quick primer on the Wiki. In essence, a water jacket is the series of passages for coolant to circulate around the engine’s cylinders to keep everything cool and operating optimally. In Elio’s case, the automaker said it used computational fluid dynamics (CFD) to optimize the prototype engine cooling scheme. Quoting the e-mail:
The cylinder head portion of the water jacket was designed with the intent of maximum combustion chamber cooling; reducing the required octane content in the fuel used which in turn allowed for higher compression ratios. The volume was kept to a minimum to keep flow velocity as high as possible. A connecting bridge was also added along the “spine” of the water jacket which had the benefits of increasing cross-cylinder flow velocity as well as eliminating air pockets that would accumulate between the cylinders. Detail was also taken to extend and loop the water passages around important cylinder head features like the intake port, the exhaust port and the spark plug, thus maximizing the cooling area.
The head gasket is the mating surface between the engine block and cylinder head and, as such, must contain some passages for coolant to travel through. According to Elio, The size, shape, and location of these orifices on the head gasket have been designed to optimize flow from the cylinder to the head portion of the engine. Elio said larger passages are placed at the number 1 cylinder to encourage coolant to flow up and over the first cylinder, then over and around the other two — more efficient than flowing coolant up and over one cylinder at a time, says Elio.
You can’t talk head gasket without talking water pump — a.k.a. the other thing that ruins your life for a few days if it ever fails on you. Elio said the water pump for the three-cylinder engine has been designed with a lower flow rate and will use curved-vane impellers, making the pump slower and reducing parasitic losses. That’s a plus when you’re dealing with somewhere in the neighborhood of 60 horsepower at the crank.
Notably missing from this missive about the Elio’s cooling system: Not a word was said about the radiator or total liquid coolant capacity. Maybe Elio is saving that for a later “Tech Talk” e-mail. We’ll be watching.