1972 Pontiac GTO - A Round-Port In The Storm
By 1972, ever-increasing insurance rates and the impact of federal emissions regulations were quickly extinguishing the fire that fueled the first musclecar era. Relegated to an option on the venerable LeMans and no longer its own product line, the GTO was in the waning days of its popularity, but it wasn't going to go out with a whimper. The optional 455 H.O. engine would see to that.
First introduced in 1971, the 455 H.O. was a logical progression of the 400 cubic-inch Ram Air IV. Like the top-dog 400, the 455 featured 4-bolt mains and a cast crank, rods and pistons. Similarly, a Q-jet on an aluminum intake manifold with a separate cast iron exhaust crossover was employed. The heads had round exhaust ports and there were streamlined exhaust manifolds as well. Though the H.O. had more cubic inches than the Ram Air IV, it had less cam, using the 068 (288/302-degrees duration with 0.414/0.413 lift) instead of the 041 (308/320-degrees duration with 0.520/0.520 lift), and less compression at 8.4:1 vs. 10.5:1 to run on regular unleaded fuel. For 1972, pumping out 300 net hp, the 455 H.O. was Pontiac's top engine option.
Ordering And Owning A Legend
This fact was not lost on SJ Baroody, Jr. of Baltimore, Maryland, who special-ordered a '72 GTO and handpicked the best performance options available: the 455 H.O. engine (code LS5) with the Air Inlet-Hood/Ram Air (code WU3) and unitized ignition (code K65), four-speed manual HD transmission (code M22) and Safe-T-Track differential (code G80).
Baroody also complimented his Goat with a plethora of convenience and appearance options including AM-FM radio (code U69), speaker-rear seat (code U80), console (code D55), Rally II wheels (code N98), power brakes-disc front (code JL2), Rally gauge cluster (code W63), rear bumper guards (code V32), air conditioning manual (code C60), dcor group (code Y80) and deluxe bucket seats (code Y90).
Baroody desired even more power and, soon after he brought his new GTO home, he ordered all of the top-end parts offered over the counter for the '70 R/A-IV (yes, they were still available) including R/A-IV heads, camshaft and 1.65 rockers. Baroody ported and polished the 71 cc chamber R/A-IV heads, which upped the compression on his GTO. He also ditched the 3.31 gears for 4.10s. He recalls, "I don't remember how the GTO performed with 3.31s. I removed them almost immediately when it was new." With the mods, the Pontiac went from a 14-second street-savvy musclecar to a 12-second contender in the quarter-mile.
The high compression ratio forced Baroody to run Sunoco 260 high-octane gasoline in the GTO. But when, in the mid-'70s, Sunoco 260 was no longer available, he removed the R/A-IV heads and reinstalled the original 111cc 7F6 heads, resulting in a lower-octane-friendly 8.4:1 compression ratio.
Baroody drove auspiciously over his 13 years of ownership, racking up only 54,000 miles on the rare GTO. But how rare is it really? Pontiac production records tell us that 635 hardtop (and 10 post coupe) 455 H.O. GTOs were produced in the '72 model year and, of this number, 310 hardtops came with the M22 four-speed.
New Caretakers
Baroody sold his GTO in 1985 and it remained in the proud ownership of Phil Ponder until 2006. Ponder remembers how excited he was when he found the Goat. "It was like bringing home a true love," he tells HPP. Ponder performed a frame-up restoration on the GTO in 1994, using the service of Rob Mount of Linthicum, Maryland, who hung N.O.S. front fenders and hood, and applied a two-step urethane/clear paint process in the original code Z (or 65) Sundance Orange color.
With the help of Chuck Roberts, co-author of the Pontiac GTO Restoration Guide, 1964-1972, Ponder spent the next nine years restoring the GTO to showroom condition. In 2003, he drove it to the GTOAA Nationals in Columbus, Ohio, where it took First Place/Popular Vote in its class.
In 2006, Lloyd Coulson of Bellaire, Texas, found the trophy-winning GTO on eBay and decided to add it to his collection of Pontiacs. Having owned five '70 GTOs, a Shadow Gold '72 GTO WW5 and two '72 Formula 455s, Lloyd knew that he would give the Pontiac the care it needed. Once delivered, he found he had very little work to do. Says Coulson, "I installed the thermal vacuum switch for the EEC system in the intake manifold coolant passage, and added the correct vacuum hoses from the EEC canister to the switch and from the switch to the carburetor. I also installed the correct rear upper A/C compressor bracket designed to clear the preheat tube, which goes from the intake manifold exhaust crossover to the passenger side air cleaner snorkel."
The code WM 455 H.O. engine is still running the R/A-IV cam and rockers. Its factory aluminum intake (No. 488945) is under the original code 7042273 Q-jet, the factory unitized distributor (No. 1112133) remains and the exhaust exits through original round-port 455 H.O. manifolds (Nos. 478141 left and 9799721 right) to a 2 1/4-inch exhaust with aftermarket mufflers. The stock bellhousing mates to the code WJ M22 transmission, which outputs power through the factory driveshaft to the once again stock code XUK 3.31 geared GM 12-bolt rear.
This GTO is also optioned with the Y99 Handling Package that features variable ratio power steering, 1 1/8-inch front and rear sway bars, specific springs and shocks, and Goodyear G60x15 Polyglas GT tires. Coulson plans on keeping this rare GTO all stock and he tells HPP that the Y99 suspension package has a lot to do with it. "It's an awesome package and really turns the GTO into a well-balanced and great-handling car. It's one of the best things about it," he says. "Thanks to the earlier restoration, it rides, drives and handles just like a brand new '72 GTO."
Now showing 70,260 miles on its odometer, this special-order GTO runs as good as it looks, posting a 13.40 in the quarter-mile at 108 mph. Coulson's plans are to install a concours correct Gardner exhaust system and to replace the engine compartment's belts and hoses with date-coded reproductions in preparation for points judging at national POCI conventions.
The '72 455 H.O. GTO marked the end of an era, but Coulson looks upon it as the high watermark. "In my opinion, the combination of the torque and horsepower of the 455 H.O. places it at the pinnacle of the musclecar engines," he tells HPP.

Photo Gallery: 1972 Pontiac GTO 455 H.O. - High Performance Pontiac Magazine

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