Robert S. McNamara

What Happened?
You may remember Robert S. McNamara as the Secretary of Defense under U.S. Presidents John F. Kennedy and Lyndon Johnson, but McNamara was also a moving force in the auto industry, where he worked at Ford from 1946 until 1961. McNamara is a nexus between world politics and the auto industry—and the timing of his work as president of Ford Motor Company interests us here. During the 1950s, when Detroit was moving toward larger, gaudier, more expensive cars, McNamara was an advocate of smaller, safer, more fuel-efficient cars. One of the last things he did before moving on to Kennedy’s cabinet was to bring the Ford Falcon into existence in 1959 as a 1960 model.

What It Caused:
As any good gearhead knows, the Falcon was the platform on which the ’64 Mustang was built. Inexpensive, lightweight, and powered by an optional V-8 engine, the Mustang singlehandedly started the ponycar revolution and became the basis for today’s performance recipe of a V-8 in a lightweight, affordable car. Without McNamara, there is no Mustang, no Camaro, no Firebird, and no ’Cuda. After McNamara became Secretary of Defense in 1961, his logistical expertise was used to preside over the escalation of the Vietnam War, raising the troop count from a mere 900 advisors in 1964 to nearly 535,000 combat troops by June 1968. Would we have been better off if McNamara had stayed at Ford?

Chrysler “Hemi” Aircraft Engine

What Happened?
Nothing spurs innovative engineering like wartime, and World War II was no exception. There are probably hundreds of technical innovations from WWII that indirectly made a mark on hot rodding, not to mention the social and economic conditions that made hot rodding thrive, but some of them are more iconic than others. While arriving too late to have a big impact on the war, Chrysler’s IV-2220 “Hemi” aircraft engine was designed to push internal combustion aircraft to new levels of performance. The experimental 2,500hp liquid-cooled inverted V-16 aircraft engine was designed by Chrysler and was Chrysler’s first “Hemi.”

What It Caused:
The Hemi is arguably the most iconic hot rod powerplant in existence, thanks to the war effort. This aircraft Hemi engine technology would eventually make its way into Chrysler automobiles in 1951 (which lasted until 1958). It then made a comeback in 1964 in its most storied 426ci variant, going on hiatus once again in 1972. Then in 2002, the third-generation Hemi appeared in its current form, where it once again ruled the road. And while much about the Hemi has changed since WWII, the basic power-producing concept of a hemispherical combustion chamber is still proving valid.

1967 Federal Clean Air Act

What Happened?
While there had been federal legislation to control pollution prior to 1967, it was the 1967 Federal Clean Air Act that first put high performance on notice: Clean up your act, or get off the road. In response to a marked deterioration in air quality, especially in urban areas, the new law was the first to put strict limits on auto manufacturers for hydrocarbon and carbon monoxide emissions.

What It Caused:
No longer would automakers get a free pass to make cars heavier, engines larger, camshafts longer, compression ratios higher, or exhaust plumes dirtier. The Big Three would have to deal with these engineering challenges head on. Through the years, federal legislation has “forced” OEMs to come by new horsepower honestly, and these efforts have yielded watershed technologies such as electronic fuel injection, exhaust catalysts, cylinder deactivation, turbocharging, stratified combustion, regenerative braking, aerodynamic styling, low rolling resistance tires, and more. The cumulative effect of these technologies has resulted in vehicle performance and power completely beyond the comprehension of a 1967-era hot rodder.

Clean Air Act Extension of 1970

What Happened?
The EPA banned the use of tetraethyl lead in 1976 as a result of the Clean Air Act Extension of 1970. No more great-smelling gas, but a bunch more “forced” technical improvements to engines and fuels. Researcher Herbert Needleman had found that higher blood levels of lead in children were correlated with decreased school performance. Needleman was repeatedly accused of scientific misconduct by individuals within the lead industry, but he was eventually cleared. Of course, today we know that lead poses a serious health threat beyond its use as a fuel antiknock additive and valvetrain protectant, but the fight all started with leaded gas.

What It Caused:
Though the Clean Air Act Extension of 1970 required the phaseout of lead tetraethyl, it wasn’t without a fight. A back-and-forth court battle between the Ethyl Corporation and the EPA dragged things out until lead phaseout could start in 1976. Lead phaseout forced manufacturers to develop other technologies with which to protect valve seats and stave off compression-related knock. If it weren’t specifically for the Clean Air Act Extension of 1970, we wouldn’t have hardened valve seats, quench-optimized combustion chambers, high-swirl ports, and all the extra horsepower that comes from them. Unfortunately, the improvement in school performance that Needleman hoped for hasn’t manifested itself.