Rajo Motor and Manufacturing
Encyclopedia
Racine, Wisconsin
Racine is a city in and the county seat of Racine County, Wisconsin, United States. According to 2008 U.S. Census Bureau estimates, the city had a population of 82,196...
in the twentieth century. The company built performance enhancing cylinder heads for Model T cars that were designed by Joe Jagersberger
Joe Jagersberger
Joe Jagersberger was an Austrian-American racecar driver.-Background:...
(Rajo Joe). The company was named by combining the "RA" from Racine and the "JO" from Joe Jagersberger's first name. The heads were sold around the world. The company's Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...
salesman Rajo Jack
Rajo Jack
Dewey Gatson, better known as Rajo Jack or his pseudonym Jack DeSoto, was an American racecar driver. He is known as one of the first African American racers in America. He won races up and down the West Coast of the United States in stock cars, midgets, big cars and motorcycles...
helped popularize the heads.
History
In 1911 Joe JagersbergerJoe Jagersberger
Joe Jagersberger was an Austrian-American racecar driver.-Background:...
retired from driving after he had one of his legs amputated. Jagersberger continued to work for J.I. Case
Case Corporation
Case Corporation was a manufacturer of construction and agricultural equipment. In 1999 it merged with New Holland to form CNH Global, a Fiat Group division...
, as he had before the crash, until he decided to go out on his own. The company was formed in 1914 as Rajo Manufacturing. Jagersberger restructured the company in October 1919 after he designed a head with double the performance of the stock Model T head.
Models
Rajo Motor started out building spark plugSpark plug
A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed fuels such as aerosol, gasoline, ethanol, and liquefied petroleum gas by means of an electric spark.Spark plugs have an insulated central electrode which is connected by...
s and other various engine parts. Jagersberger began manufacturing heads for The first design was the Model 30 which had 4 exhaust ports and one intake port all on the right side of the head. The Model 31 had two intakes on the right and four exhaust on the left. The Model 35C, first known as the "Improved Rajo Valve-in-Head" and later as the Model C had two intakes and three exhausts on the right. The Model A used the stock intake ports on the block. It had two exhaust ports on the right. His Model B two intakes on the right and four exhausts on the left. It came in three versions. The BB featured a higher compression ratio
Compression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
and the BB-R also included two spark plug
Spark plug
A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed fuels such as aerosol, gasoline, ethanol, and liquefied petroleum gas by means of an electric spark.Spark plugs have an insulated central electrode which is connected by...
s per cylinder.
Chevrolet work
He also offered a modification to the 1941-52 Chevrolet "stovebolt
Chevrolet Straight-6 engine
The Chevrolet inline 6 was Chevy's main engine from 1929 , through 1954, and was the base engine starting in 1955 when they added the small block V8 to the lineup. It had finally been completely phased out by 1990 in North America, but Brazil held on to their fuel-injected straight-6 through the...
" L6 OHV 15 bolt head, which added another set of 3 intake ports above the 3 originals, to permit adding (an) extra carburetor(s) on a separate manifold.
Jagersberger died in 1952. The company closed in 1980.