Chalmers Motor Company was an American car company headquartered in Detroit, Michigan. The company started in 1908 and continued producing high-end vehicles until 1923, when it merged with Chrysler.
"Six-30"/ "Y"
The "Six-30" consisted of Models 35-A ("5-15" for 5 passenger and 115-inch wheelbase), 35-B (or "7-22" for 7-passenger body and 122-inch wheelbase), 35-C, and 35-D. The car's balanced crankshaft and a new Morse silent timing chain gave it a reputation for a quiet and smooth ride. Later designs introduced a lower silhouette, one-piece windshield, and even disc wheels.
To overcome the poor fuel available at the time, the "Hot Spot" and "Ram's Horn" were introduced in 1918 to improve engine performance. The "Hot Spot" and "Ram's Horn" warmed up the air-fuel mixture.The "Six-30" came in a wide variety of body styles and wheelbases to seat between 2 and 7 passengers.
In late 1923 customers could purchase the Model Y with an optional hydraulic four-wheel brake system for $75 based on hydraulics that had been initially developed for Lockheed.
Source: Wikipedia