The 1966 Street Hemi


When the 426 Hemi was introduced in 1964, it was strictly a race engine. On February 23 of that year four Hemi powered Chrysler products swept the Daytona 500, finishing 1-2-3-4. This single event caught the racing world by surprise and eventually prompted Nascar to impose stricter production rules on Chrysler. This was something racing organizations seemed to have a penchant for, beginning with the Briggs Cunningham engines. 

In a way, you couldn't really blame them after what Chrysler often tried to pull. Nascar and various other organizations were trying to build audience level at their events, and they felt that the best way to do it was to have the entrants drive identifiable cars that everyday people could go out and buy. Chrysler, however, had other ideas and often developed engines that nobody could get unless their name happened to be Petty. The new rules were simple; sell what you race to the general public, or stay home.

To comply with the new rules, Chrysler would have to produce several thousand hemi engines per year instead of only a few blueprinted racing engines. They would have to put them into ordinary production vehicles and sell them to ordinary people. Well, maybe ordinary people with brain tumors. Gone would be the scam of making 50 cars and selling them all to racing teams. Bob Rodger ordered that the hemi be made available to the public, and laid out some parameters. The new engine was to have dual quads, cast iron manifolds, forged pistons, and preferably hydraulic lifters, which did not happen until 1970. All 1966-1969 hemi engines had solid lifters. They were built upon the basic design of the wedge RB engine, not the older 392 hemi design.

While the engineers tooled up the new engine, Chrysler sat out the 1965 Nascar season. The end result of the Rodger project was the badly detuned street hemi, which first appeared in 1966 Dodge Coronets, Chargers, and Plymouth Satellites. It came through with Chrysler's favorite ratio, the 3.23 axle. Combined with a Torqueflite and the hemi's long legs, this combination contributed greatly to the street hemi's lackluster acceleration. It would do about 3,000 miles per hour in Drive, but who cared? It wouldn't break out of the 14's in the quarter mile. Guys who ordered 4.10 gears fared somewhat better, but needed to live very close to a gas station. 

The street version differed from the race engine by virtue of a lower compression ratio of 10.25:1 and much milder valve timing. Cast iron heads, intake, and exhaust manifolds were used instead of aluminum, presumably to add weight and slow the cars down. Carter AFBs with chokes would replace the Holley racing carburetors, and there would be manifold heat. My friend Joe tried to compensate for the extra weight of the monster motor by drilling about 500 holes in the inner fender wells of his Satellite. It didn't work; the car was still an oinker. You could strain pasta under the hood after that, though.

Very little changed inside the 426 Hemi throughout its production life other than minor differences in camshaft design. More duration was added in 1968, and a hydraulic camshaft was used beginning in 1970. Chrysler never changed the engine's advertised horsepower and torque ratings, which stood at 425 hp at 5000 rpm and 490 foot pounds of torque at 4000 rpm. Four bolt mains were standard on every 426 Hemi block.
In addition to being an obvious ploy to get the banned  engine into the lineup at Nascar events, the street hemi was billed as the replacement in the MoPar lineup for the dual quad 426 max wedge, which nobody in their right mind ever tried to drive on the street anyway. Cars with solid tappets, no manifold heat, no chokes, and 13.5 compression don't make very good grocery getters. 


Contrary to popular myth, most guys who bought "muscle cars" wanted something they could start without using a can of ether and two truck batteries. They also wanted to be able to drive it around without having the thing overheat, flame out, foul a set of plugs, and drink half a tank of Sunoco 260 every 50 miles. The most popular choices up until that point had been the 383 with 330 horsepower, and the 426 street wedge with 365 horsepower. I looked under a lot of hoods in high school, and I never saw any super stock 426 wedges looking back at me. When the hemi arrived, The venerable 426 street wedge  was unceremoniously dumped. Big mistake.

"What the hell is wrong with this thing?"

That was the first thing I said in 1966 when my friend Joe mashed the accelerator to the floor of his 1966 street hemi powered Satellite and very little happened. The 1966 GTO he had owned up until that time had actually seemed faster than the new Plymouth. The victim of a rear ender, the GTO was no more. Joe just shrugged it off.
"It isn't broken in yet," he said.
"I think it's just broken, period," I laughed. He didn't think it was all that funny. Our friend Bob Mackey, 300K owner and 413 expert, lived across the street from Joe. "C'mon," he yawned one evening, stretching mightily. "Let's see whatcha got there." He smirked at me, because he already knew. 

Joe and Bob got into the Satellite and took off. I waited at Bob's house. After a few minutes, I heard screeching tires and roaring hemi mufflers in the distance. The roar faded, and ten minutes later the Satellite pulled into the street, idling erratically. Bob got out and waved to Joe, who went inside his house. Bob came over and shook his head. "What a pig," he giggled. "The K would eat that thing alive."

The Plymouth never improved. Joe took it to a racing shop for a tune up, but it still wouldn't drop below 14.5 in the quarter mile. Most of his runs were in the 15 second range. I always wondered about Joe's car, because magazines of the day were getting much better times from the hemis they tested. Come to find out, the cars were "set ups" sent to the magazines by dealers who specialized in racing. Joe's car finished the quarter mile in second gear with a little rpm to spare, which led me to think maybe they had accidentally installed 2.76 gears in the rear end. We counted the turns of the drive shaft one day just to make sure it had 3.23s. It did. 

Joe finally got sick of the car's lackluster performance. We had been making forays to Dover Drag Strip in Wingdale, New York, and our friend Al Laidlaw's stock 390 horsepower 427 Corvette was routinely stomping the daylights out of the hapless hemi. Even the 300K beat it, which was the last straw. With nothing more than slicks, the Vette consistently banged out 12.7 quarter mile times. Joe's solution was to give the Plymouth ten gallons of aviation gas spiked with something he wouldn't tell us about, but it made your eyes water, so take a guess. The hemi made one good 13.5 run, and returned to the pits barely running with smoke pouring out of the engine compartment. 

"You blew a hose," Bob Mackey chortled, elbowing me. He knew. He always knew. Joe didn't say a word, he simply hooked up the tow bar. The engine had suffered severe cylinder head damage, and required a rebuild. Some time after the rebuild, the hemi grenaded and was replaced by a used 361. I have no idea what caused it, Joe just said it blew apart one night. He was married by then and had lost interest in racing, so the hemi went to the junkyard. Back then all it was worth was scrap weight, and he certainly wasn't going to spend mucho dinero to buy a long block. 

In 1970 I was in the market for a muscle car myself, and passed on one of the few hemi Barracuda convertibles ever made mainly because of what Joe had experienced. Besides, the car was basically a piece of crap. The Challenger was worse. As always, who knew. People will buy anything today if the production numbers are low. They never stop to think about why they were low.

Don't get me wrong here; the race hemi is probably the best racing engine produced in modern times. The street hemi, however, was just an overweight, detuned chink of iron whose only job was to get its bigger brother to the prom. Unfortunately for car collectors, most of which have never driven one of these beasts or ridden in one, the race motor's reputation was automatically and unfairly conferred upon the lesser engine.

One thing has to be in place for a car to achieve legendary collector status; the car must have something that was unique and ground breaking for its day. The hemi engine didn't really qualify, because Chrysler had already cranked out millions of hemis in the 1950s. The 426 street hemi wasn't exactly unique, either, because it didn't deliver what it promised. That leaves us with the old stand by, production figures. Too many collectors place too much importance on low numbers without giving much thought to the reason for the numbers. 

"They only made 20 of these!" collectors will proclaim. "There are only three left."

Okay, they only made 20. That's because out of millions of potential customers, only 20 people wanted the car. Hmmm. You could apply the same standard to other cars as well; how many 1959 four door Chevy Biscayne six cylinder sedans with no options were produced? How many are left? Want one? Me neither. Low numbers, though. Go figure. 

Unsuspecting investors who think they are purchasing some sort of rocket ship on wheels would be sadly disappointed if they actually took the hemi off the trailer once in a while and beat on it a little bit. Hemi cars are now routinely priced in the $100,000 to $200,000 range, with one collector whose sanity has to be in serious question parting with 2 million for a Barracuda, of all things. Comparable wedge cars are about one quarter to one fifth of that. Okay, they didn't make that many hemi cars, so sue me. There was a reason for that;  word got out that the engine was very expensive as an option and a complete dog on the street. 

Owners of street hemis soon found out that there were a lot of cars that should be avoided at stop lights. Well tuned tri power GTOs would hang with you all day long, 427 Fairlanes would make you think your engine had shut off by mistake, and you damn well better avoid those little Camaros with the insane 375 hp 396 under the hood. And don't even think about playing with a 427 / 425 hp Corvette.

The performance level everybody expected from the street hemi simply didn't materialize. With the option costing $1105 against a base price of $2695, we were expecting uncontrollable, tire incinerating acceleration and maybe an occasional wheelstand. What we got was a fourteen second quarter miler that got 0-60 in the low 7 second range. We already had that with any good running 426 street wedge Belvedere. Put this into perspective.......the option price was 40 percent of the cost of the car. That would be like paying $12,000 for an engine option on a $30,000 car today, and getting nothing much for it. Would you be happy? Would you tell all your friends? You betcha. Nobody, and I mean NOBODY who knew my buddy Joe ever bought a hemi. 

During the course of the hemi's introduction, one of the car magazines took one and installed headers, an STX 23 Racer Brown cam kit, and a set of 4.56 gears. The transformation was amazing.......the car immediately cracked 12 flat. Why couldn't the factory have built the engine that way? They could have, but chose not to for some reason. Maybe they were afraid it really would be uncontrollable, and somebody would either kill themselves or somebody else and sue Chrysler. 

Later on that year, Chrysler replaced the street wedge 426 with what is probably the best street engine they ever made, later to be known as the 440 Magnum. It was in a few Chargers and Coronets around town, and they really ran. They had the hemi for lunch in the quarter mile, although if you wanted to push it to 140  the hemi would pass you by.
In 1966, the FBI ordered two Coronet 4 door hemi cars. One is in the Don Garlits museum, (see gallery) the other reportedly was sold to a collector. 
 It's really a shame the way it worked out.....the street hemi cars cost a lot of money in the day, and they just didn't deliver.

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