Life is a compromise. Nothing of note ever gets done without two opposite ends meeting in the middle; everyone gives up a little something in pursuit of the greater good. The inability to compromise, to demand everything and be unhappy with anything less, is unproductive, says the conventional wisdom. Yet the strongest, most enduring creative endeavors are often the work of a singular vision. DaVinci, Van Gogh, Picasso—none of them worked by committee.
Half-measures and "good enough" weren't the answers for Mark Avakian of Apache Junction, Arizona. As a mechanic for a major airline—convincing wounded birds to fly again—he knows about quality, safety, speed, and redundant systems in equal measure. His vision? To build (with his own hands) a GTO that could do anything he demanded. Hurtle down the quarter-mile in 11 seconds. Corner like a late-model WS6 Trans Am. Cruise in supreme comfort while blasting the stereo and keeping cool in the hot Arizona summer sun. And make it home on its own power, even if something should go wrong. His canvas? A Tiger Gold desert rat GTO liberated from an estate sale in 2009. For $6,000, he bought a complete and straight—if tired—automatic '66, sans driveline.
The Powerplant and Drivetrain
Hidden beneath the blinding polishing work, you’ll find a ’73 455 block stuffed with a 4.5
Let's start with the engine Mark built, since most of the mechanical fortifications stem from its 498.3 rwhp at 5,500 rpm and 556.2 lb-ft of torque at 4,400 rpm. He started with an XA-code '73 455 block, performed a 0.030-overbore, and fitted an RPM 4.500-inch-stroker crank for a whopping 495 cubes. A Holley 950 Ultra HP carburetor with No. 94/94 jets—fed by two Holley HP150 fuel pumps (one picking up fuel from the front of the tank, one from the rear), an Aeromotive regulator set to 7 psi, and an -8 fuel line—sits atop a port-matched Edelbrock Victor intake. The balanced reciprocating assembly consists of Ross forged flat-top pistons (11.2:1 compression using aluminum Edelbrock 87cc round-port heads), Total Seal rings, and Eagle H-beam forged rods with ARP 2000 hardware.
A Comp Cams hydraulic roller cam (248/254 degrees duration at 0.050, 0.600/0.618-inch lift, installed 5 degrees advanced) tickle Crower stainless 1.65:1 roller rockers via chromoly pushrods; Lunati beehive valvesprings attach to stainless Ferrea 2.11/1.77 valves utilizing 10-degree retainers and locks. The round-port E-heads were built by Butler Performance and were ported to flow better than 300 cfm at 28 inches of pressure.
Internal lubrication is handled via a Butler 80-psi Pro Series pump plumbed to two separate chassis-mounted oil filtration systems and is fed via a seven-quart Canton pan. An MSD ignition system (Pro-Billet distributor, Digital 6+ amplifier, Blaster SS coil, 8.5mm wires) set to 36 degrees total all in by 2,900 rpm keeps the NGK plugs igniting the air/fuel mixture; a March serpentine pulley system cleans up the front of the engine, and a Ron Davis radiator cools it.
In case the 3-inch pipes aren’t loud enough, the press of a button can bypass the full exh
Spent gasses are sorted via a set of Jet Hot-coated Doug's Headers with 1.875-inch primaries and 3.5-inch collectors. The rest of the exhaust depends on Mark's mood. For mellow over-the-road trips, the 3-inch twice-pipes blow through a pair of Flowmaster Super 44 mufflers that don't muffle so much as shape sound; most cars under full throttle don't sound as nasty as this one at idle. Then, for those occasional short bursts of energy—required when it's vital to show the delicate styling of his louvered taillights disappearing into the distance—Mark flicks a switch and the Race Ready 3.5-inch electric cutout butterflies change position, creating unmuffled excitement that exits right below the seat of his pants.
The five-speed TKO 600 transmission is one of many contemporary touches. First gear is a steep 2.87:1; with the 4.11s out back, the gear multiplication works out to 11.795:1. That (despite the Eaton posi) means that the vanity registration tag, TIRFRIR, is less a license plate than a statement of intent. Yet Fifth gear is Overdrive, which means final drive is knocked down to an effective 2.62 on the open road; the engine is barely off idle while loping along at highway speeds. An 11-inch Centerforce Dual-Friction clutch and 30-pound Hays flywheel ensure a smooth step-out every time.
With nearly 500 horses on the ground, the rest of the chassis required upgrading too. To start, the perimeter frame was boxed and powdercoated for strength and durability. Mark chose UMI tubular front and adjustable rear upper and lower control arms, UMI antiroll bars (1.25 inches in front, 1 inch in back), a QA1 coilover shock system (the compactness of which helps that fat 3-inch exhaust clear both the rear axle housing and the floor), and urethane bushings everywhere.
Billet Specialties makes a 17-inch wheel called GTO, so what could be a more natural addit
Arguably, the front suspension of any ’60s car is the most ripe for reconfiguration. The o
QA1 coilovers and UMI adjustable upper and lower control arms keep the ’67 GM 12-bolt (sho
Mix in Wilwood spindles, Moog steering linkage, a UMI "Wonder Bar" frame stiffener, and the steering box from a '96 Jeep Grand Cherokee—"It's a quick-ratio box with excellent road feel. The '60s box is like driving in the snow," Mark says. The new suspension components provide updated geometry that encourages the heavy nose to more eagerly follow the contours of a twisty road.
Binders are a Wilwood four-piston system with cross-drilled 12-inch rotors and a Wilwood master cylinder and proportioning valve, all powered by a Tallon Hydraulics Hydroboost system. Unsurprisingly, all of the brake lines are also custom-made stainless. Billet Specialties GTO 17-inch wheels and sticky Nitto 555 tires (245/45s in front, 285/40s in back) provide style, stance, and grip.