Tom Hoover: The "Father of the Hemi"
Tom Hoover, known as the “Father of the Hemi,” was born in Huntingdon, Pennsylvania, a town about an hour and a half west of Harrisburg. The son of an auto mechanic, Hoover grew an interest for cars at an early age. His first car was a 1952 DeSoto, which sported a Hemi under its hood.
Hoover graduated high school in 1947 and went on to pursue a mechanical engineering degree at Juanita College in his hometown. The college didn’t have a mechanical engineering program, so he took chemistry and, later, physics instead.
In 1948 he joined Pennsylvania’s National Guard, and was deployed in December 1950 for 19 months to serve in the Korean War. When he returned home, he got his undergraduate degree in physics and Master’s degree from Penn State University.
In 1955, Tom Hoover joined Chrysler Corporation, earning a Master’s degree in automotive engineering at the Chrysler Institute.
At Chrysler, performance projects, and the Ramchargers
One of Hoover’s first projects at Chrysler was the Bendix fuel injection system (Electrojector), an early version of today’s electronic fuel injection systems. He later moved on to work in the engine lab to study engines, particularly the English straight six. He also was involved in the development of the successful Slant Six Hyper-Pak project.
We each had our own project and in concert we enjoyed getting together, going to the drag strip and talking and whatnot. But there was no combined effort, and ... the formal organization of the whole thing began in the Fall of 1958. Several of us gathered in Wayne Erickson’s apartment for the first meeting in the evening. We didn’t have officers or anything like that to form the club. So we did, but again, it was entirely independent. Strictly for fun and so forth.
Hoover said the Ramchargers name came from the new-at-the-time ram manifold and the “charge” from charging cylinders with air. He designed the first multiple tuned length inlet manifold during the Ramchargers’ early years, which was used successfully in a race car in 1960. Hoover himself was the national record holder and class winner in C/Gas/Automatic, driving a ’57 Plymouth convertible with a 392 Hemi. He had designed the intake manifold, the first street-functional ram manifold.
After working primarily on their own cars, the club decided to work on project vehicles, the first being the “High and Mighty” 1949 Plymouth business coupe. As Tom Hoover said, “It was a super low-budget operation. Various interested people contributed largely in what was becoming their field of expertise. For example, the first engine for the car was put together by myself and Danny Mancini. It was a 354 Dodge Truck engine, truck-like, big truck, which had dropped an exhaust valve, sodium-cooled exhaust valve. The only money we spent on it aside from gas and so forth which we could liberate at Chrysler was a set of pistons and we had a camshaft ground for it.”
The Ramchargers then worked on a 1961 Dodge sedan for racing with support from Dodge and Plymouth officials. The goal was to create a more appealing line of cars for the younger market, a concern initially brought up to Townsend by his two teenage sons. The club received performance parts, including the engine, from Chrysler, built up the Dodge, and took it to the 1961 U.S. Nationals. The crew made it to the semi-finals, but a synchronizer in the three-speed manual transmission broke. They repaired it and won on Monday.
While Chrysler had not been particularly interested in racing development, newly appointed Chrysler president Lynn Townsend changed that, allocating resources and appointing Tom Hoover as race program coordinator for the engineering division.
The Ramchargers set out to create a drag racing performance package, starting the Max Wedge program in October 1961. Hoover’s duty as master engineer for the Max Wedge cars (as a whole) was to apply all their racing knowledge to the raised B engine, testing different options on the dynanometer; the engine ended up with two four-barrel carburetors, bigger valves, and a ram intake. The next step was the Cross-Ram Wedge, with extra-long runners; to gain length, each cylinder bank was fed by a carburetor on the opposite side of the engine, with the intake tubes crossing in the middle, to create a strong ram-air or supercharging effect (hence the name “cross-ram”). The mid-size cars were sold starting in the spring of 1962 (as 1962 models), and they were successful immediately.
The wedge engines were successful, but the competition was rapidly gaining, and the Tom Hoover and Don Moore decided they needed to mate the RB block with hemispherical heads, similar to those used on Chrysler’s first V-8 engines. Tom Hoover was instrumental in developing the resulting 426 Hemi, and he is often called “the father of the Hemi.” These engines, the first to get the “Hemi” name, were different in many ways from the originals, but kept the same intake-to-exhaust-valve angles, mainly, according to Willem Weertman, because there was no time to test for the optimal angle.
The Hemi was successful in NASCAR’s February 1964 race at Daytona Beach, and dominated both the NHRA and AHRA, too. Hoover said:
When we got the green light to go ahead and adapt the Hemi head to the big V engine, we realized that one day it would be something revered, that it would be something that everyone would look back on as something very special indeed. ...
In ’64, the proudest moment to me was the first time the R car went 130.06 at the Nationals to set the record. So ’64 was a good year, then things started to get funny. ... Then the wheelbase change, we went through fuel injection and to nitromethane fuel. And finally, by ’67, a matter of having family commitments and being the long weekend and all this stuff, it came to a point where all the Ramchargers just kind of shut down. ... It’s been a life’s frustration to me. It’s very difficult for people on the outside to understand that the Ramchargers, although heavily supported by Dodge ... it was not a formal Chrysler Engineering race effort.
Part of the Hemi’s success was a strong shakedown. Mike Buckel remembered, “In what proved to a great piece of foresight, Tom Hoover rented the Fontana Drag Strip for shake-down testing of the Hemi cars. All four A/FX cars were there along with the Super Stock cars from the same teams. Then came the big disappointment: the Hemis were the same or slower than the wedges.” The problems were worked out and the Hemi went on to dominate racing for years.
To continue competing, the Chrysler had to have a minimum of production cars equipped with the same “basic” engine configuration, leading to the birth of the street Hemi. The Street Hemi was not in the plans at the beginning, but Tom Hoover said that it proved to be easier to produce than the Cross-Ram Wedges, because it could come down the line complete with exhaust manifolds (while the Cross-Ram engines had to have their manifolds fitted later). He and Frank Bilk had tilted the combustion chamber to prevent the exhaust rocker from being too long; this resulted in a narrower engine, which allowed for a standard "body drop" with the B-bodies in the Dodge Main factory.
Hoover also became involved with the Lil’ Red Express truck, one of his last projects at Chrysler. He bumped up the 360’s power by adding a “hot” camshaft out of a 340 V8. He wanted to use a fresh air system that would channel cold air into the engine, but that didn’t make it into production.
In 1979, Hoover resigned from Chrysler; he worked for General Electric through 1984, then moved on to Bosch (in Massachusetts) and designed fuel supply systems at Walbro Orbital. The story did not end when he retired; Hot Rod reported that he met with Chrysler engineers when they were working on the modern 5.7 Hemi, and at least three of his suggestions were immediately adopted. These were using twin spark plugs, raising the camshaft (to shorten pushrods, reducing valve train inertia and allowing simpler exhaust rocker arms), and adding squish area (to make light load/low speed efficiency better and to reduce emissions).
Mike Buckel on Tom Hoover
Ramcharger Mike Buckel wrote,
I joined Chrysler in June of 1961 and within a week was involved with the Ramchargers. The High & Mighty had been recently scrapped, but there was very little discussion of that car. There was, however, quite a bit of discussion, lead by Tom Hoover, of the tragic death of Wayne Ericson during the 1960 Nationals at Detroit Dragway. Wayne and his wife were very close friends of the Hoovers.
Wayne was the National Record Holder and class winner in B/Gas. His car was a ’54 Dodge with a 354 Hemi engine. He was the Chrysler fuel injection guru, working on a system to counter the Rochester system on Chevrolets and Pontiacs, and his car was so equipped. There was a fuel controller mounted under the center of the dash (in the plane of the flywheel). He flim/flamed his way through NHRA technical inspection and was allowed to race. On his last time trial, reaching for 2nd gear, the clutch blew and the scatter shield, having experienced many explosions, said, “I quit.” Parts came up and took out the fuel control and started a fire. Wayne bailed out and expired about 10 days later. Racing attire back then was a tee shirt.
Tom was the National Record Holder and class winner in C/Gas/Automatic. His car was a ’57 Plymouth convertible with a 392 Hemi. The intake manifold was Tom’s design and was the first street functional ram manifold (with short tubes on one side and longer tubes on the other). After Wayne’s death, Marge Hoover forbid Tom from ever driving a race car, and as far as I know, he did not.
As the master engineer for the Max Wedge cars, beginning in ’62, Tom assured [racers] that the combination clutch housing/scatter shield was totally effective. I watched several tests in the mechanical lab where clutches were spun up to over 10,000 rpm. A clutch housing could withstand some large number of clutch explosions. Tom also specified the clutch be the right kind of iron, that had twice the strength of the other.
We were racing at Vineland, New Jersey in ’62 when a Max Wedge Plymouth blew the flywheel and many parts escaped the car. A large chunk of flywheel came down near where we were pitted and cut its way to the ground through a Ford. Hoover became very upset and rushed over to interview the driver. His response was, “everybody knows that Chrysler clutches are no good so I installed a Chevrolet clutch and flywheel.” Tom walked away just shaking his head.
As the Ramchargers cars became faster and faster Tom was always quick to remind us, “remember Wayne Ericson.” This was emphasized when we got into the nitro stuff.
Tom was the primary guy that came up with nicknames. In the Engine Lab there was Chester Gasket, Dipstick Larue, Orin Blowby, and the manager, Ev (Evinrude) Moeller. He used to walk around the halls of engineering shifting gears up for acceleration and down for the turns. He had special disrespect for the manager of the Carburetor Lab, who had managed the plant that built tanks for the Korean War. These tanks were noted for being parked under a tree having the engines changed. Tom is a Korean War Vet.