There were exciting things were underway inside of Chevrolet in 1956. The Corvette received its first body refresh, there was an optional dual-quad, 225-horsepower 265 engine (RPO 469, $172.20) and a Special High-Lift Camshaft option (RPO 449, $188.30) that bumped the power of the dual-quad 265 to 240 horsepower, plus fuel injection was in the works.
Corvettes set records at Daytona Beach and took a class win at the 12 Hours at Sebring; memorialized with the now classic “Real McCoy” print ad. Things were looking up for Corvette.
Meanwhile, an unlikely series of events happened in Corvette creator, Harley Earl’s house; that could have become the Z06 of its day. Earl’s son Jerry bought a Ferrari with the intention of going racing. When Harley learned of his son’s plans, he hit the roof! “No son of mine is going out there with an Eye-talian car!” he allegedly bellowed. As GM’s VP of the Art and Color Division, Earl could do anything he wanted, so he charged top designer, Bob Cumberford, with the task of designing a race car for Jerry. The completed car was called “SR-2.”
Cumberford and his team took the all-new 1956 Corvette body and extended and lowered the nose, created a vented hood, short twin wind screens, side air scoops on the doors and a low vertical stabilizer fin on the trunk lid. Decked out with Halibrand knock-off wheels and metallic blue paint, the SR-2 was a great-looking Corvette. Jerry picked up his customized, basically stock Corvette on May 24, 1956, and raced the car at Elkhart Lake, Wisconsin, through the summer months. The car was a hit, thanks to its unique looks, but at 2,900 pounds, it was heavy and quickly ate up its brakes. The SR-2 was not competitive.
Earl’s successor, Bill Mitchell, was two years away from taking over as VP of Design had enough clout to order an SR-2 built for him. The Jerry Earl SR-2 was more of a styling study, Mitchell directed his SR-2 to be an all-out lightweight racer.
The body was so thin that the fiberglass matting can be seen at certain angles. While the nose of Mitchell’s SR-2 was similar to Earl’s car, Mitchell’s SR-2 had a tall vertical stabilizer fin that was integrated into the driver’s headrest. Hidden inside the headrest were a rollbar and a racing fuel filler cap for the 48-gallon fuel tank. The side scoops were ducted through the rear of the door and doorjamb, directly to the rear brakes. Yes, functional external rear brake scoops, just like a modern Z06. The interior had lightweight fiberglass racing bucket seats with racing seatbelts; a full instrument cluster; a custom-designed teakwood steering wheel with a column-mounted 8,000-rpm tachometer; stainless steel gas, brake and clutch pedals; lightweight door panels with tuck ’n’ roll door panels and a single door-close strap.
Under the hood of Mitchell’s SR-2 is a tricked-out, Smokey Yunick-built, fuelie 283 small-block Chevy engine. Keep in mind that the SBC had just come out. Advanced parts included Packard Electric solid-core stainless steel high-tension ignition wires and a higher-voltage ignition coil. The generator was mounted on the left side to give the tension-side of the belt better grip on the water pump pulley. Inside the engine was the Special High-Lift (Duntov) Cam. Most unique was the fiberglass ram-air box that connected to the driver-side inner fenderwell and was ducted to the front grille opening. The engine dynoed to 310 horsepower, a lot for 1956.
The suspension was straight out of the RPO Racer Kit parts catalog and included heavier front springs, five-leaf rear springs, larger 13/16-inch front sway bar, larger diameter 1-3/8-inch stiffer shocks, quick-ratio 16.3:1 steering and rear torque rods (traction bars). The rear axle was the new Multi-Disc Limited-Slip Positraction unit. Brakes were aluminum-finned drums with cast-in steel liners and Bendix Cerametalix brake shoes.
The SR-2 used every aerodynamic trick of the day. “Streamlining” was the buzzword of the day, just like today’s “downforce.” The SR-2 had headlight cones, short windscreens and a faired in headrest with an aircraft-style vertical stabilizer fin for high-speed stability. We see the same concept on the modern prototype road racing cars.
Although aerodynamicist Wunibald Kamm invented what we call today the “Kammback” design that is very aerodynamically efficient, automotive designers and stylists favored the tapered teardrop-style for high-speed cars. While not as extreme as the long tapered speed record cars from Europe, the design of the 1953-’60 Corvette’s rear section tapers down.
Because of the rear vertical stabilizer fin, the large trunk section was hinged at the back and opens to the back. Both the front and back of the SR-2 were void of bumpers and are very clean-looking.
The SR-2’s Smokey Yunick-built engine was special inside and out. Production 1956 Corvettes had 265-cid small-block engines, but the SR-2 had the 283-cid engine. The unreleased Rochester fuel-injection system was part of the SR-2’s engine setup and was part of the fuelie’s development program. Deep inside the 283, the bumpstick was a pre-production high-lift “Duntov” cam. Steel-tube headers were a novel item in 1956. Yunick’s engine dynoed to 310 horsepower.
What’s most amazing about Mitchell’s 2,200-pound SR-2 is that it was built by fabricators at Chevrolet that were not race car builders, but were damn good builders. Later, they built Duntov’s Corvette SS. But the SR-2 met the same fate as the Corvette SS; the 1957 AMA Racing Ban. In December 1956, Mitchell campaigned the car in the Nassau 70-mile Governor’s Trophy Race finishing 10th overall. In February 1957, Mitchell took his SR-2 to the Daytona Beach Speed Week, outfitted with an enclosed canopy, full Moon disc wheel covers and semi-enclosed rear wheels, a red and white stripped rear fin and Zoomy headers! Buck Baker drove the SR-2 to a Modified Class win with an average standing-mile speed of 93.047 mph, and was first in the Flying Mile at 152.866 mph. Then in March 1957, Mitchell’s SR-2 competed at the 12 Hours of Sebring, coming in 16th place overall.
After the AMA Ban, the SR-2 was sold and bought, and was eventually owned by Don Yenko’s private plane pilot, Cookie Knuth, who didn’t do much with the car. In 1980, Chevrolet development engineer Bill Tower bought the car from Knuth and set it aside, as he was very busy working for Chevrolet. After some consideration, since the SR-2 was only missing a few parts, Tower chose to simply put it back together.
Tower had an interesting encounter with retired Bill Mitchell in a meeting that was supposed to last 15 minutes that turned into 3 hours. The first thing Mitchell said was, “You got my damn car and I want it back! That one got away from me. I got in a lot of trouble with those cars.” The two men benched raced about all kinds of things, with Mitchell telling Tower that he’d help him get a set of fiberglass buckets for the SR-2. When the two parted, Mitchell said, “You take care of that car and don’t wreck it! That car is very special to me!”
Tower’s SR-2 is driveable, but he hasn’t taken it out on the streets take after a near T-bone incident. Now he only drives the SR-2 after it has been transported to special events. In 1982, Tower was invited to bring the SR-2 to the Daytona 500 to the Chevrolet tent along with the new IROC Camaros. Bill Mitchell and Bill France, Sr. were there as well. After “a few,” Mitchell and France wanted to take the SR-2 out for a few laps, to which Tower said, “Like hell you will!” At the 1986 Indy 500, Tower and Pace Car driver General Chuck Yeager took a few laps in the SR-2. Later in 1986, Tower was invited to display the SR-2 at a special Chevrolet event on Mackinac Island in Michigan. Chevrolet luminaries such as Clare MacKichan, Vince Piggins, Bill Mitchell and other GM executives were there along with Linda Vaughn and singer Neil Diamond.
Since then, Tower doesn’t show the car very often and it is mostly seen via visits to his private museum. In 2016, retired VP of Global Design Ed Wellburn visited Tower and was totally blown away with the SR-2. He couldn’t get over how many key design elements on the C7 were also on the SR-2. Tower says, “Of all of my cars, the SR-2 is most special to me. Look at everything that’s in the car. And it was built in 1956!”
The airbox was a trick setup in 1956 and showed how serious the SR-2’s designers were about looking for as much horsepower as they could get. The concept is alive and well and is today a popular and easy add-on for C5, C6 and C7 Corvettes. And there it was, back in 1956!
Although on the surface the SR-2 was a toy for Bill Mitchell to go racing with, the SR-2 was an official Development car. Tower says that the numbers on the stamped metal plate attached to the top of the radiator indicate the different projects that were done to the SR-2. The overall SR-2 project didn’t have an “X” or “EX” number indicating that it was an experimental car.
The Halibrand 15x6 wheels were cast in magnesium. Take note of the five slots in the wheel’s design. That style was used when Kelsey-Hays developed the 1967 steel Rally Wheels. Knock-off wheels helped speed up pit stops, but many knockoff wheels came off of cars because the spinners weren’t properly tightened.
The SR-2 was a serious lightweight race car, but the spartan interior was nicely finished. The teakwood and stainless steel steering wheel went through over a dozen different diameter and offset variations until Mitchell got what he liked.
Even the dash was made of thin fiberglass. Note that the dash is unique, as the production Corvette’s dash had a mirrored hump on the passenger side. Serious racing instruments mounted to brushed-metal plate replaced the stock instruments.
When Tower bought the car, the original SR-2 seats were long gone. During his 3-hour meeting with retired VP of Design, Bill Mitchell, the design legend told Tower, “I’m going to help you with your SR-2 project.” A few weeks later a set of fiberglass seats arrived at Tower’s home. The seats had RPO number molded into the fiberglass, indicating that at some point, Chevrolet was considering offering racing seats as part of the Corvette’s RPO program.
The doors were gutted of their window mechanisms to make room for the side scoop vents that lead back to cool the rear brakes. The interior door panel was tuck ’n’ roll aluminum with vertical ribs and a door closure pull.
The finish and attention to detail on the SR-2 is extraordinary. While the SR-2 race car was built by fabricators that were not race car builders, they were the same people that built the Motorama cars, so they were highly qualified craftsmen. The instrument panel looks like a component from a Ferrari. Note the metal pedals that didn’t come on Corvettes until 1997.
The one single element on the SR-2 that did not belong on the car is the big toothy grille. But, you have to consider that the build of the SR-2 was being directed by Harley Earl and Bill Mitchell. Both men had an acute sense of how things presented and looked. Even the 1957 Corvette SS racer had a big grille up front.
The functional rear brake scoops was one of many design elements that blew away retired GM Global Design Chief, Ed Welburn, when he visited Tower’s museum. Welburn said, “We didn’t put this on the Corvette until the 2001 Z06!”
In our time, we don’t associate Corvettes with NASCAR. But from 1936-1958 Daytona Beach was where speed records and Stock Car racing happened. Tower’s SR-2 and his Betty Skelton 1956 Corvette both set speed records on the nearly 2-mile-long beach straightaway part of the Daytona Beach and Road Course in 1957.
“What’s with the big fin?” you ask. Speed records provided street cred for performance cars back in the day. Logic of the day said; since vertical stabilizers are essential for airplanes and jets, a tall, long fin could only help a speed record seeking race car.
For many years road racing cars had to carry a spare tire. In case of a blowout the driver was required to change his own tire off on the side of the track. Because of the headrest and rear fin, the trunk lid had to be hinged from the rear. Tower has a unique lead mallet designed by Proto for knock-off Indy car wheels. The slightly loose handle gave a second hit on the knock-off spinner.
The twin windscreens were beautifully handcrafted by the Chevrolet master fabricators.
The vented hood was another detail that rocked Ed Welburn. This functional design element didn’t make it into production until 2014. Venting the hood helps the engine keep cooler, plus reduces frontend lift. This concept would have helped the 1963-’67 Sting Rays a lot.
Bill Mitchell hated hood pins that stuck up and had to have their pin retainer and attachment cord in the wind. He insisted on flush-mounted, aircraft-style latches for the hood and trunk.
The fuel filler door is located just behind the headrest. Note the rollbar tubes. NASCAR didn’t like exposed rollbars back then. The filler cap indicates that Mitchell and his team intended to race the car the following June at Le Mans. See the ring tab that’s close to the fill cap latch? A special seal was put on the fuel cap at the beginning of the race. The seal could not be broken before a car’s first pit stop for fuel.
The SR-2 sure makes Marilyn look good, doesn’t it? Marilyn Monroe was on her way to Miami for a screening of her new movie Bus Stop. At the Sebring Airport she got a ride to the racetrack on the Thursday practice session. She posed with several cars, including the SR-2. Attendees and drivers couldn’t believe it was her.
Here is Bill Tower at the inaugural Amelia Island Concours d’Elegance receiving the Earl B. Hadlow Award for his 1956 SR-2. From left-to-right is; Sting Ray and Daytona Cobra designer Peter Brock; National Director for Hospice; seated in the SR-2 is Betty and Bill Tower; standing next to Tower is Sir Stirling Moss; representative from Barnette Bank; and stylist Larry Shinoda.
Photo: Bill Tower Photo Collection
The “Jet Age” began in the late 1940s and by the mid-’50s car designers were adding jet aircraft styling elements to their car designs. This photo was taken at the GM Tech Center before being transported to Daytona Beach. The SR-2 was decked out with an enclosed canopy, full Moon discs, semi-enclosed rear wheels and Zoomie headers. Tower pointed out that because of the small 283-cubic-inch engine, the dragster-style headers didn’t provide enough scavenger effect and didn’t help the car’s performance.
Photo: GM Archives
Here’s the tricked out “Jet Age” SR-2 on at the Daytona Beach Speed Week event. The SR-2 took a Modified Class win with an average standing-mile speed of 93.047 mph and was first in the Flying Mile with a speed of 152.866 mph. Impressive for a 310-horsepower car 283 car.
Photo: Bill Tower Photo Collection
The SR-2 raced at Sebring in 1957 with Paul O’Shea and Pete Lovely doing the driving. Race car suspensions have come a long way since 1957.
Photo: Bill Tower Photo Collection
Posing in a relaxed moment, perhaps after Marilyn’s visit, the SR-2’s pit crew and drivers Paul O’Shea (with the sunglasses) and Pete Lovely. Sebring is hallowed ground for Corvette racing history. All of the greats of Corvette lore—past and present—have been there.
Photo: Bentley Publishing
Photography by Scott Teeters