How many of us lament the fact that we didn’t have the forethought to squirrel away our favorite Pontiac back in the day to preserve and enjoy it for years to come? Well, Mike Clay of Keyport, New Jersey, doesn’t have that regret. He purchased this ’73 Pontiac Grand Prix SJ brand new, and when he became a car salesman and was given a demo to drive, he decided to retire his GP from regular road duty just eight months after he purchased it.
Living the “life of Riley” as a weekend fun machine has resulted in the Starlight Black SJ accumulating just 15,400 miles since its purchase, and inside storage has preserved its original paint, interior, suspension, and drivetrain. In fact, Mike says that except for the tires and an underhood cosmetic restoration, the GP remains as it was delivered to him in 1973.
“In 1972, I got the itch to buy something that was sporty and had a luxury feel to it,” Mike remembers. “I looked at T-Birds, Rivieras, and Monte Carlos. In the end, I found some to be too big, and others not flashy enough or quick enough. Then I checked out the Grand Prix SJ. I was taken with the fact that it had a 455 engine, which I knew was fast. It had style and luxury, and I liked that it had bucket seats.”
Mike says he knew the Super-Duty 455 engine was optional and he probably would have specified it, but it wasn’t available when he ordered the car, and as we know, ultimately, it wasn’t installed in a GP.
Downes Pontiac in Matawan, New Jersey, had a GP prominently displayed in the showroom. “I immediately fell in love with it and placed an order in October 1972,” Mike says. The order was for an SJ with the striking color combo of Starlight Black with white interior and a host of options (see the window sticker).
Mike’s hope of taking delivery of his new GP within a few weeks were dashed when he learned that he would be placed on a three-month waiting list, which was later extended to five months, resulting in delivery in March 1973. “Actually, I was kind of relieved since the car didn’t experience the harsh winter months,” he says.
Custom finned wheel covers...
Custom finned wheel covers were part of the SJ package. The original Uniroyal Radial GR70-15 tires were replaced with 215/70R-15 Symmetry Michelins in 2009.
Under the hood, the 8:1 compression 455 pumps out 250 hp and features a Q-jet on an iron intake with EGR, 4X heads with 2.11/1.66 valves, and an 067 cam with 273/289 degrees duration and 0.410/0.414 lift. The bottom end consists of a two-bolt-main block and cast crank, rods, and pistons.
Spark is delivered by the rare Unitized Ignition system, also part of the SJ package, which was a forbearer to HEI. The exhaust is full duals fed by log-type manifolds. The Turbo 400 was the only trans offered, and it sends torque to a 3.08-geared rear.
The braking system consists of 11-inch front discs and 9.5-inch drums in the rear. The SJ package includes GR70-15 radial tires, and adds computer-designed springs, bushings, Pliacell shocks, and a 0.812-inch rear swaybar (to augment the 1.125-inch front bar) to exploit their ride and handling qualities.

The 250-horse 455’s engine...

The 250-horse 455’s engine bay is quite clean. About seven years ago Mike had the front clip removed to repair the radiator support. At the same time, he decided to have the underhood accessories, engine, and compartment cosmetically restored. The engine has never been removed from the GP.

Mike relates, “Approximately...

Mike relates, “Approximately five years ago I was searching for an original Unitized distributor cap. I was worried I would have difficulty finding a replacement, since Unitized ignition is so rare. In searching for this part that probably cost less than $20 originally, the prices had climbed incredibly.”

According to the owner, the...

According to the owner, the Starlight Black paint on his ’73 Grand Prix SJ is original.