World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0001235862
Reproduction Date:

Title: Offenhauser  
Author: World Heritage Encyclopedia
Language: English
Subject: Kurtis Kraft, 1950 Indianapolis 500, 1960 Indianapolis 500, 1959 Indianapolis 500, 1979 SCCA/CART Indy Car Series
Collection: Formula One Engine Manufacturers, Indianapolis 500
Publisher: World Heritage Encyclopedia


Industry Automotive
Founded 1934
Founder Fred Offenhauser
Headquarters United States
Products Automobiles, Automotive parts
An Offenhauser sprint "midget" racer
Two views of an Offenhauser midget car racing engine - polished for display

Offenhauser was an American engine design that dominated American open wheel racing for more than 50 years and is still popular among vintage sprint and midget car racers.


  • History 1
  • Common Offenhauser Engines 2
  • World Championship Indy 500 summary 3
  • References 4


The Offenhauser engine, familiarly known as the "Offy", was developed by Fred Offenhauser and his employer Harry Arminius Miller,[1] after maintaining and repairing a 1913 Peugeot Grand Prix car of the type which had won the Indianapolis 500. Impressed by the double overhead cam, four-valve-per-cylinder design, which was a great leap forward at the time, they designed an engine on similar principles. Originally, it was sold as a marine engine. In 1930, a four-cylinder 151 cu in (2.47 l) Miller engine installed in a race car set a new international land speed record of 144.895 mph (233.186 km/h). Miller developed this engine into a twin overhead cam, four-cylinder, four-valve-per-cylinder 220 cu in (3.6 l) (3.6 L) racing engine. This would be used in midgets and sprints into the 1960s,[2] with a choice of carburetor or Hilborn fuel injection.[3] When Miller went bankrupt in 1933, Offenhauser bought the shop and the rights to the engine. He and another Miller employee, draftsman Leo Goossen, further developed the Miller into the Offenhauser engine. Then in 1946 the name and engine designs were sold to Louis Meyer and Dale Drake. Meyer was bought out by Dale, wife Eve and son John in 1965. From then until Dale Drake's son John Drake sold the shop to Stewart Van Dyne, the Drake Family designed and refined the engine until its final race days. It was under Meyer and Drake that the engine dominated the Indy 500 and midget racing in the United States.[4]

One of the keys to the Offenhauser engine's success was power. A 251.92 cubic inch (4,128.29 cm³) DOHC twin-cam four-cylinder racing Offy with a 15:1 compression ratio and a 4.28125-by-4.375-inch (108.744 mm × 111.125 mm) bore and stroke, could produce 420 hp (310 kW) at 6,600 rpm (1.77 hp per cubic inch (81 kW/L). Other variants of the engine produced up to 3 hp per cubic inch (137 kW/L). Another reason for the engine's success was reliability; unit construction (no separate cylinder head) meant the engine was not vulnerable to head gasket or cylinder stud problems and allowed for higher cylinder pressures.

From 1934, through the 1970s, the Offenhauser engine dominated American open wheel racing, winning the Indianapolis 500 27 times. By then, the company had already been sold, right after World War II, to Meyer-Drake, who continued to build the engines. From 1950 through 1960, Offenhauser-powered cars won the Indy 500 and achieved all three podium positions, winning the pole position in 10 of the 11 years. In 1959 Lime Rock Park held a famous Formula Libre race, where Rodger Ward shocked the expensive and exotic sports car contingent by beating them on the road course in an Offenhauser powered midget car, which was normally considered competitive for oval tracks only.

When Ford came on to the scene in 1963, the Offy began to lose its domination over Indy car racing, although it remained a competitive winner through the mid-1970s even with the advent of turbocharging. Before turbo boost limits, over 1,000 bhp (750 kW) could be attained using around 44.3 psi (3.05 bar) boost. The final 2.65-litre 4 cyl Offy, restricted to 24.6 psi (1.70 bar) boost pressure, gave 770 bhp (570 kW) at 9,000 rpm. However, the Cosworth DFX soon proved to be unbeatable and the Offy's last victory came at Trenton in 1978, in the hands of Gordon Johncock's Wildcat. The last time an Offy-powered car raced was at Pocono in 1982 for the Domino's Pizza Pocono 500, in an Eagle chassis driven by Jim McElreath, although two Vollstedt chassis with Offenhauser engines failed to qualify for the 1983 Indianapolis 500.

Common Offenhauser Engines

Offenhauser produced engine blocks in several sizes. These blocks could be bored out or sleeved to vary the cylinder bore, and could be used with crankshafts of various strokes, resulting a wide variety of engine displacements. Offenhauser (and Meyer-Drake, in later years) frequently made blocks, pistons, rods, and crankshafts to specific customer requests. However, certain engine sizes were common, and could be considered the "standard" Offenhauser engines:[4]

  • 97 cu in (1.59 L) - to meet the displacement rule in many Midget series
  • 220 cu in (3.6 L) - displacement rule in AAA (later USAC) sprint cars
  • 270 cu in (4.4 L) - displacement rule for Indianapolis 500 under AAA rules
  • 255 cu in (4.18 L) - for Indianapolis (during the 1930s fuel consumption rules)
  • 252 cu in (4.13 L) - displacement rule for Indianapolis 500 under USAC rules
  • 168 cu in (2.75 L) - displacement rule for turbocharged engines at Indianapolis (to 1968)
  • 159 cu in (2.61 L) - displacement rule for turbocharged engines at Indianapolis (1969 and later)

World Championship Indy 500 summary

Season Cars Entered Winning Driver Second Driver Third Driver Polesitter Race Report
1950 31 Johnnie Parsons Bill Holland Mauri Rose Walt Faulkner Report
1951 32 Lee Wallard Mike Nazaruk Manny Ayulo Report
1952 30 Troy Ruttman Jim Rathmann Sam Hanks Fred Agabashian Report
1953 32 Bill Vukovich Art Cross Sam Hanks Bill Vukovich Report
1954 34 Bill Vukovich Jimmy Bryan Jack McGrath Jack McGrath Report
1955 35 Bob Sweikert Tony Bettenhausen Jimmy Davies Jerry Hoyt Report
1956 32 Pat Flaherty Sam Hanks Don Freeland Pat Flaherty Report
1957 31 Sam Hanks Jim Rathmann Jimmy Bryan Pat O'Connor Report
1958 31 Jimmy Bryan George Amick Johnny Boyd Dick Rathmann Report
1959 33 Rodger Ward Jim Rathmann Johnny Thomson Johnny Thomson Report
1960 33 Jim Rathmann Rodger Ward Paul Goldsmith Eddie Sachs Report

In their 11 World Championship years, The Meyer-Drake Offenhauser engine partnered for at least one race with the following 35 constructors:


  1. ^ "Fred Offenhauser".  
  2. ^ Circle Track, 9/84, pp.82-3.
  3. ^ Circle Track, 9/84, p.83.
  4. ^ a b Offenhauser by Gordon Eliot White
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.