When Car and Driver strapped its test gear to a mid-size Pontiac in February of 1968 and watched it hit 60 mph in 5.2 seconds, the numbers read more like a Hemi Charger or a big-block Corvette than a Tempest-based muscle car. The secret wasn't anything Pontiac sold off the showroom floor. It was a 428 cubic inch V8 quietly swapped in by a Detroit-area dealership that had spent the decade bending General Motors' own rulebook. If you love GTOs, this one belongs on your radar right next to the other Pontiac muscle currently turning heads on Motorious.Image courtesy of MecumThe dealership was Royal Pontiac of Royal Oak, Michigan, and the car was a Royal Bobcat 428. To understand why a dealer-installed engine swap was even necessary, you have to rewind to early 1963, when GM ordered its divisions out of factory racing and capped engine displacement in intermediate cars at 400 cubic inches. That ceiling left the GTO, the Chevelle SS, the Buick GS400, and the Olds 4-4-2 all stuck at the same number just as Mopar was turning the 426 Hemi and 440 Magnum loose on the street. Pontiac, a brand built on speed under John DeLorean and Jim Wangers, needed a workaround. It found one by quietly pointing customers toward Royal Oak.How Royal Pontiac Became Pontiac's Unofficial SkunkworksRoyal had been Pontiac's shadow performance arm since the late 1950s, when owner Ace Wilson Jr. started campaigning a tri-power Catalina at the drag strip and stocking factory racing parts behind the service counter. The dealership's race cars were a serious presence at the 1960 NHRA Nationals, and once GM pulled out of racing in 1963, Royal effectively became the factory team in everything but name. Pontiac specialist Milt Schornack, later joined by Dave Warren, ran the wrenching, and DeLorean made sure many of the most important GTO press cars passed through Royal Oak first, including the legendary 1964 "ringer" that Car and Driver famously compared to a Ferrari 250 GTO.Image courtesy of MecumThe 428 Swap And The Bobcat TreatmentBy the time the redesigned 1968 GTO arrived, with its curvy semi-fastback body, color-matched Endura nose, and available hidden headlights, the Royal formula was well sorted. For $650, roughly $6,000 in today's money, Royal would pull the factory 400 and drop in a 428 lifted from the full-size Pontiac line. Because every Pontiac V8 shared the same external dimensions, the swap was all but invisible to anyone peering under the hood. Schornack's crew didn't simply bolt the bigger motor in, either. They reworked the top end, valve gear, ignition, and carburetion using Royal's signature Bobcat package, which bundled thinner head gaskets to bump compression, a re-jetted Rochester Quadrajet, a distributor recurve kit, and a handful of other tuning tricks. The finished engines were said to be good for well over 425 horsepower.Image courtesy of MecumThat Car and Driver test car, fitted with a Turbo-Hydramatic and 3.55 gears, ran 0 to 60 in 5.2 seconds and the quarter mile in 13.8 seconds at 104 mph. For context, a stock Ram Air 400 GTO of the era needed roughly 14.5 seconds to cover the same quarter. The Bobcat wasn't a night-and-day improvement off the line, but it pulled noticeably harder in the midrange and kept reaching deep into the top end, which is exactly where a heavier 428 earns its keep.The Car Heading To MecumThis particular example is a documented, two-owner Royal Bobcat 428 wearing an unusual Verdoro Green and Red two-tone exterior over an Ivy Gold interior. It has been through a concours-style restoration using OEM and NOS parts throughout. Power runs through an automatic backed by a Hurst Dual-Gate shifter, then out to a Safe-T-Track differential on a 3.23-ratio 10-bolt rear axle, with Ram Air induction up top, chrome Hurst wheels and Firestone Wide Oval tires at the corners, plus a rear deck spoiler and hideaway headlights.AdvertisementAdvertisementWhat really sets it apart is the equipment list, which runs to 35 factory and dealer-installed options. Inside there are bucket seats with headrests, a power driver's seat, a center console, the Rallye gauge package with a hood-mounted tachometer, factory air conditioning, cruise control, an AM/FM radio with reverb, and an 8-track player. Among the odder period touches are a still-unused Sony "Micro TV," complete with its case and quarter-window antenna, and a GM mini air compressor in the trunk for topping off tires at the track. The car comes with a thick file of receipts dating back to new, along with the original owner's manual and service literature.Image courtesy of MecumGM finally dropped the 400 cubic inch ceiling for 1970, when the GTO got its own factory 455, but by then the muscle car era was already fading under insurance surcharges and looming emissions rules. That makes the Royal Bobcat 428 a snapshot of a very specific moment, arguably the quickest brand-new A-body money could buy in 1968 if you knew exactly who to ask. It's due to cross the block with Mecum in late July, and you can keep up with more auction-bound muscle like it over on Motorious.⚡️ Read the full article on MotoriousSign up for the Motorious Newsletter. For the latest news, follow us on Facebook, Twitter, and Instagram.
