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Illustrated Corvette Series No. 144 - Penske 1966 L88 Corvette - "The First L88 Racer"

Roger Penske began his racing career in 1958 at the Marlboro Motor Raceway in Maryland. Just two years later, he won the Sports Illustrated SCCA Driver of the Year award. Penske’s prowess on the track got the attention of Zora Arkus-Duntov, and he was subsequently hired as a driver for the 1963 Grand Sport Nassau assault. This led to a friendship with Duntov and helped pave the way for Penske to become a successful race-team owner. At the time, race cars were becoming brutally fast, and many talented drivers were being injured or killed. In 1965 Penske decided to hang up his helmet and focus on his new Cadillac dealership. Then one day, Duntov called.

The Corvette chief engineer was working on a new secret weapon—called the “L88”—to take on Shelby’s 427 Cobras. Duntov wanted to know if Penske was interested in receiving a pre-production L88 to use for a little “field testing.” Duntov had always been Corvette racer’s best friend, but the L88 was to be a Corvette kit racer like no other.

In 1962, Chevrolet began work on a new, large-displacement version of the 348/409 truck engine. A few prototypes were “let out the back door” to be used in NASCAR competition, and these caused quite a stir. Car magazines called the new engine “Chevy’s Mystery Motor.” The new big-block finally made it into production in 1965 as a 396; a 427 followed a year later. Although these high-performance mills represented a radical step forward, Duntov was already thinking ahead.

Duntov had always made sure there were off-road parts available for the Corvette, but this latest effort was to be the most comprehensive racer package ever offered by Chevrolet. The star attraction was, of course, the L88 engine. Duntov had wanted an all-aluminum engine for the Corvette since the ‘57 “Q” concept, and the alloy-headed L88 was a first step in that direction. The L-88 was essentially an L72 427 on steroids. Packing 12.5:1 compression, solid lifters, a racing camshaft, a big 850 Holley carb with no cloak, an aluminum intake manifold, and a TI ignition, this was not a street-car engine. The rest of the package included J56 heavy-duty brakes, a 36-gallon fuel tank, an F41 heavy-duty suspension, a prototype Positraction differential with 2.73 gearing, an M-22 rock crusher transmission, an off-road exhaust, a teakwood steering wheel with telescoping column, heater and radio deletes, and a prototype cowl-induction hood. Needless to say, Penske accepted Duntov’s offer.

Penske worked out a one-race sponsorship deal with Sunoco and assembled a team to run in the 24 Hours at Daytona. At Duntov’s suggestion, he hired California Corvette racer Dick Guldstrand to help prep the L88 and serve as one half of the driving team (along with George Wintersteen). When Guldstrand picked up the car at the St. Louis assembly plant in January, it wouldn’t start. The disgusted workers pushed it off the line and told him, “This is yours, kid. We don’t want anything to do with it. Just get it out of here.” Then Guldstrand drove the car 800 miles to Penske’s Pennsylvania shop, in January, with no heater and just a furniture blanket to keep warm.

Once in the shop, the car was taken apart and prepped for racing. Several hundred pounds were removed, largely through the use of aluminum replacement parts. Magnesium racing wheels with wide tires necessitated small aluminum flares on the wheel wells. The rear fenders were also bulged out, and the trailing arms were notched. Suspension bushings were replaced with aluminum spacers, dual electric pumps and an engine-oil cooler were added, and extra-large header side pipes were installed. The interior got a roll bar, racing gauges, and shut-off switches. Racing headlights with clear covers were also added, and every nut and bolt was safety wired. As is the case with many race cars, the team worked around the clock up to the day of the event.

All long-distance racing is filled with drama, and the Penske L88 effort was no exception. The race’s sponsor, Pure Oil, took issue with the car’s Sunoco 260 gas, and tech inspectors didn’t like its aluminum fender flares. Nevertheless, the Vette ran one of the quickest qualifying times ever at Daytona. While all this was going on, Traco Engineering had a balanced-and-blueprinted 550-horsepower engine in transit. The team would install the fresh engine the night before the race.

It turned out to be a very tough contest. In the middle of the night, the Corvette T-boned a slower competitor, blowing off most of its front end. The team wired the body together and taped flashlights to the front fenders for light, leaving Guldstrand to drive by following the taillights of the leading Ferrari. Despite this handicap, the team won First in the GT class and 11th overall. The L88 hit 168 mph on the Daytona back stretch.

Sunoco was so pleased with Penske’s performance, it extended his sponsorship to cover the 12 Hours at Sebring, where the L88 won the GT class and came in Ninth overall. Roger Penske’s new career as a team owner had officially begun. Penske sold the car after Sebring, and subsequently it was raced in many different forms. It was even converted into a street machine at one point. The car’s current owner, Kevin Mackay, did a total restoration in 2001 and has since earned the NCRS American Heritage Award. Today, the L88 prototype is completely functional and considered by many to be one of the finest examples of Corvette racing history in existence. - K. Scott Teeters

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Illustrated Corvette Series No. 27 - 1966 427 Corvette - "The Mark IV Grows Up"

Chevrolet had all the bases covered for 1966. The bar had been significantly raised at both ends of the performance spectrum. The base Corvette engine was now a 300 - horsepower small-block, while the top position was held with the 425 - horsepower, big-block 427. Performance took a quantum leap.

The 1965 big-block 396 was bored out to 427 cubic inches for 1966, taking the street- driven Corvette to undreamed of high performance. The factory power rating was 425 horsepower at 5,600 rpm. However, the real redline was more like 6,500 rpm, producing over 450 horsepower! This was 75 horsepower more than the 1965 fuel- injection setup. Duntov joked that 31 cubic inches of cast iron is a significant weight savings. The Corvette was now at the top of the performance feeding chain.

Subtle changes for the 1966 Corvette made it stand out from previous cars. The egg-crate grille and hub caps were obvious on coupes and convertibles. "Corvette" script on the hood was new and the roof vents on the coupe were gone. The interior trim was changed, in addition to new optional head rests and hazard lights. If you could tolerate the exhaust noise, side pipes were a bargain at $131.65.

Racers and wanna be's had plenty of hardware to choose from. The L72 427/425 engine cost $312.85. The M-22 "Rock Crusher" four-speed was $237, and the special heavy-duty brakes cost $342.30. The F41 special front and rear suspension was a super deal at $36.90.

Although the base Corvette cost $4,295, down $26 from 1965, total production for 1966 was 22,940, down from 1965's total of 27,720 cars. GM didn't mind, since the press was gushing all over the new 427 Corvette. Tests from 0 to 60 mph ranged from 4.8 to 5.7 seconds with quarter mile times of 12.8 to 14 seconds. Some saw top speeds of between 130 and 152 mph, depending on gearing and the driver's guts.

1966 was supposed to be the last year for the Sting Ray design, but making the Mako Shark styling streetable for '67 was a big challenge. As hot as the '66 Corvette was, the '67 was about to get even hotter. - K. Scott Teeters

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lllustrated Corvette Series No. 28 1966 Mako Shark II Show Car Corvette
"The Running Prototype"

When the Mako Shark II was first shown at the April 1965 New York Auto Show, jaws dropped and the automotive press gasped. However, making a beautiful clay show car is one thing, making a functional road version is a completely different story.

GM tech experts Ken Eschebach and Art Carpenter headed up the crew that put every conceivable performance and luxury goodie you could think of into the running Mako Shark II. The chassis and running gear used standard 1966 Corvette parts. Under the hood was the brand-new 427 Mark IV engine coupled with the not-yet-available-in- the-Corvette three-speed Turbo Hydra-Matic transmission.

The entire front end tilted forward like an XK-E Jaguar. The headlights were made up of three quartz-iodide beams that were covered with "eyelid" panels. The top surface of the hood had cooling vents and round lids for fluid refills. The windshield wipers were hidden in a closet at the base of the windshield. At the back end, the window slats, bumper and spoiler were all electrically controlled from the interior. The seats were in a fixed position, while the gas and brake pedals were adjustable. Seat frames had racer-like, four-point seat belts. The roof- mounted headrests were adjustable, and had speakers connected to an AM/FM radio. Lights and windshield wiper controls were on the turn signal stalks and the dash had neon digital readouts. The car used seventeen electric motors to power various features.

In October 1965 the Mako Shark began a six month European tour and was the "avant garde" machine. For a show car, the Mako Shark was the closest to an actual production Corvette. Over 30 years later, it's still a stunning machine. - K. Scott Teeters