1966: Why Chrysler put a monster on the street
Geoff Stunkard - March 03, 2014 08:08 AM
This is the carb layout and air cleaner used on the Street Hemis through 1968. Tony D’Agostino collection.Geoff Stunkard
Jere Stahl won the NHRAs World Championship in Stock Eliminator with a new Street Hemi Belvedere. Don Snyder collection.Geoff Stunkard
The 1966 model lines for Chrysler featured crisp lines thanks to designer Elwood Engel; a Dodge Charger and a Plymouth Sport Satellite.Geoff Stunkard
This Plymouth, a survivor car in the Tony D’Agostino collection, features the one thing that warned the GTO owner in the other lane what was about to happen. A little tag on the fender…Geoff Stunkard
Just six days later, on January 12, 1965, a letter giving the basis for a Street Hemi combination, with minor changes from the race package, was sent back to begin development
Over the years, a lot of has been written about the reasons for the Street Hemi being unleashed by Chrysler on the highways and boulevards of America in 1966. The most-oft cited reason was to return the engine to NASCAR, where it had been ruled ineligible for competition since it was not a production-vehicle engine.
There were other ones.
One, an important one, was Stock Eliminator drag racing. On January 6, 1965, a letter came from executives Bob Cahill and Bob Rodger to members of Product Planning on the viability of creating a production-line Hemi car suitable to Stock Eliminator racing. Having a current year car in A/S was important, as the 1965 cars were running Super Stock and the steel-nosed Max Wedge cars were in the lower categories. Just six days later, on January 12, 1965, a letter giving the basis for a Street Hemi combination, with minor changes from the race package, was sent back to begin development.
The second reason for the Street Hemi was what GM was doing; by 1965, all the GM midsize lines had a “musclecar” offering to follow up the GTO that Pontiac had unleashed in 1964. There was now a Buick GS, an Oldsmobile 4-4-2, and a Chevelle SS. Chrysler already offered the 426S street wedge, a single-four-barrel, low-compression version of the Max Wedge. Available in the Sport Satellite and Coronet 500 line, this was the largest street engine in this size body from any manufacturer.
Bob Rodger, Special Car Manager and Chief Engineer, Chrysler Product Planning, gave an excellent summary of these facts in September 1966. Testing required a series of 400 drag strip runs on street tires without breakage to develop driveline reliability for the package, with only limited factory warranty available. NASCAR did play a role in the Hemi becoming a street motor. When the motor was announced and then released as a legitmate option, Richard Petty won a few events toward the end of the 1965 season.
The Street Hemi received production line changes – iron heads, inline carburetors, a heated intake manifold, short cast iron exhaust manifolds – and slight detuning, with 10.25 compression and less cam timing. The rest was pretty close to what had been on the race motor. The driveline was reworked for power.
In 1966 only, the Hemi was available in any B-body if you knew how to order it. None of the 1966 models had the decals, add-ons, and wild paint of the later muscle car era. Just little 426 Hemi tags on the front fender, a healthy lope from the cam and exhaust, and long black rubber streaks from Goodyear Blue Streak tires left on the pavement behind it…
(Geoff Stunkard, former editor of Mopar magazines, is presently writing an overview history of Chrysler’s Race Hemi engine for Cartech books to be released in 2015. He will be highlighting Hemi heritage on this 50th Anniversary for Cars & Parts throughout 2014.)