Mopar Heritage

High-Performance

Pioneer

Mopar background

Who is the father of the HEMI® engine? Tom Hoover is the consensus answer for the 426 HEMI, but what about the first Generation HEMI engine—the Chrysler FirePower V-8, introduced in 1951? We think that, if there is a “father” for this engine, he would be James Zeder.

James C. Zeder, Chrysler Vice President and Chief Engineer during the post World War II decades, was the much-younger brother of the legendary Fred Zeder, one of the famous “Three Musketeers,” Zeder, O. R. Skelton, and Carl Breer, who helped Walter P. Chrysler in the founding years of the company. His older brother was a legendary practitioner of the engineering arts—giving Chrysler robust and reliable—if not exciting—cars and trucks. James was just as capable but had an added dimension. He appreciated the excitement that was possible when technology was taken to the limit of the engineer’s imagination.

When Chrysler embarked on the long-term study of engine technology that led to the first-generation hemispherical V-8 engines, James Zeder was a leader of the effort as the company considered all the high-performance auto and aircraft engines of the world—starting with the dawn of the internal combustion engine.

Bob Cahill worked in the engine lab at that time under John Platner, director of experimental engine development. Cahill remembers the exotic European engines that were tested, including an Alfa Romeo DOHC six and a Riley two-cam pushrod hemispherical-head four-cylinder. The tests confirmed what Zeder already knew—that the hemispherical combustion chamber in a V-8 engine was the answer.

He and engine development supervisor William Drinkard promoted it in the face of the elder Zeder’s preference for a more conventional layout. James and Drinkard won the battle and the HEMI was born in 1951 with the Chrysler FirePower V-8.

Tom Hoover Chrysler Engineering

Chrysler President Ed Quinn (L) and VP-Chief Engineer James Zeder pose with the 271 cid Chrysler FirePower Indy engine. It was the result of Zeder’s early HEMI® engine performance development. It made 350 horsepower at 5600 rpm.

To James Zeder’s possible surprise (and delight), the engine was immediately adopted for racing. Here’s what he said in an October 1952 engineering paper about the Chrysler plans for future development of the engine: “The course which we set for yourself— [was] one of orderly progress with no fireworks—only FirePower! Then we met the hot-rod boys—or rather they adopted us with all the gusto attending induction into any other tribe of wild Indians [we’re sure he would choose another way to say that today] … it was a pleasure and, in many ways, an inspiration to meet a group of men in whom are rekindled the enthusiasms of an earlier era; men to whom owning and driving a car are sport and adventure, and not merely a chore inherited by default from the streetcar motorman.

“Nor has the association been technically unprofitable. The boys may not always have the solution to the differential equations, and are sometimes impatient of questions involving ‘why?’, but they have had the opportunity and the interest to find out ‘how?’; and many of their answers are remarkably good.” He obviously noticed, and was impressed by, the HEMI engines showing up at the drag strips, dry lakes and the Bonneville salt flats—and the road courses of America, not to mention HEMI -powered Chrysler sedans winning in NASCAR and in the Mexican Road Race.

Cast-Iron Header

This high-horsepower version of the FirePower engine was dressed up and used in the Chrysler K310 show car of 1952. It shows the “streamlined” exhaust manifolds that were part of Chrysler’s performance experiments.

Inspired by the hot rodders, Zeder embarked on an all-out program to improve the HEMI engine’s performance, and he left no stone unturned. His engineering departments investigated compression ratios to confirm their benefits, but concentrated on volumetric efficiency—the ability of an engine to breathe—by means of larger valves, better-flowing ports and intake manifolds with multiple carburetors— and even fuel injection.

There were separate high-torque and high-horsepower developments. The high-torque option (photo this page) had what might be the first “tunnel ram” manifold. This all led to associations with some interesting projects, namely Briggs Cunningham’s Le Mans efforts that gave new respectability to the Americans and to the HEMI, and also Chrysler Corporation’s successful attack on the Indianapolis Speedway during the summer of 1952 that led to an even more successful counter-attack by the Indy establishment that effectively shut the program down. John Platner and Don Moore were deeply involved in building the “Indy” engine, with the collaboration of Zeder, Ray White, John Platner, Mel Carpentier, William Drinkard, and Ev Moeller (the latter would lay out the 426 HEMI for engine design chief Bill Weertman).

Max Wedge 426-III

A high-torque development engine. Was this the first tunnel ram manifold?

But Zeder saw benefits for high performance that transcended motorsports. His words in the 1952 paper demonstrated an appreciation of how high performance could offset the effects of tight oil supply 57 years ago(!): “In recent years, the hoary specter of petroleum depletion has retreated, but not vanished. Should politics or geology make it brazen enough to threaten again ... It will be necessary to preserve gallons of crude oil ... and for this purpose the high compression engine may well come into its own … as the compression ratio is increased, both power and thermal efficiency are increased … This interchangeability of power and economy is fundamental; for any increase in specific power may be expended to decrease size, which requires less work and automatically improves economy.”

His words predicted that, in the interest of fuel economy (not to mention emissions abatement), the industry someday would introduce smaller engines with higher specific power. There was a flurry of such activity as a result of the Arab oil embargo of 1973 and subsequent tightening of Corporate Average Fuel Economy (CAFÉ), but 2009 has seen the U.S. Congress authorize a huge increase in CAFÉ standards while the Environmental Protection Agency (EPA ) was poised to implement new carbon dioxide emission standards, which is equivalent to requiring greater fuel economy.

Not only that, but Congress was debating the institution of regulations to reduce greenhouse gas emissions by 17 percent by 2020 (as provided by House Resolution 2454—the Cap And Trade Bill). Zeder’s prediction had come true, so we are now seeing a huge interest in small engines with high horsepower through high compression, turbocharging and other “hot rodding” methods. Zeder was more than a one-dimensional thinker, having the breadth of knowledge to see the automobile in the universe of human interest. He would have been comfortable today, marrying high performance with efficiency in a world he saw coming a half century ago.

Courtesy of Mopar Magazine