Now displacing 462 cubes, the engine features a Holley carb, Performer RPM intake, ported E-heads and a moderate CompCam. A reproduction fiberglass ram air pan (base) works with open hood scoops and a factory steel upper ram air pan to provide cold air intake. The upper ram-air pan came with the 400 hood and neither is original to this Bird. A Be Cool radiator, a Vintage Air Gen II system and a March serpentine belt system add flash and function.
The Drivetrain
Though it entered life with a 250 OHC-6, by the time Baril bought the Bird it was already fitted with a desirable, yet tired, 428 engine. Via boring the block to 4.180 and installing a 4.210 stroke 455 crank, the 428 grew to a 462 engine. Baril performed the engine build and the installation in his home garage with the help of friend Mark Robertson of Gainesville, Florida, who worked on Top Fuel dragsters for many years. The rotating assembly uses a stock 455 crank connected to stock cast rods that pump CP forged dished pistons. A TRW pump draws oil from a Milodon pan to lubricate the internals and the factory windage tray saves a few ponies.
Edelbrock 72 cc aluminum heads were ported and blueprinted by Butler Performance of Leoma, Tennessee. CompCam's hydraulic flat tappet cam delivers 224/230-degrees duration at 0.050 and 0.524/0.528-inch lift with a 106-degree LSA. The pushrod holes were elongated for use with CompCam Energizer 1.65:1 ratio aluminum roller rocker arms, which compress CompCams 987 springs to open Ferrea SS 2.11/1.77 valves. Compression checks in at 9.8:1
A Carter electric fuel pump with built-in regulator feeds a Holley 770cfm Street Avenger carburetor with vacuum secondaries and an electric choke, which sits on top of a polished Edelbrock Performer RPM intake. To increase spark discharge, Baril installed an MSD 6AL ignition box and an MSD Blaster 2 coil. Spark travels from the MSD distributor through MSD wires and to NGK Iridium plugs. Exhaust exits through 1.875-inch Doug's Headers with 3-1/2-inch collectors and a stainless steel ceramic-coated exhaust with 3-inch H-pipe, Flowmaster mufflers, 2.5-inch tails and 3-inch Magnaflow angle-cut double wall T304 stainless steel tips.
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The interior features Fiero front seats and original back seats covered in leather. The door panels are completely hand-fabricated. | 
Here's what 15 years parked under a tree can do for your Pontiac. Note the rare Chia Pet option. |
The 462 outputs power to a TCI Saturday Night Special 2,000 rpm stall converter connected to a Turbo 400. A B&M trans cooler provides extra protection and shifts are handled by a B&M Quicksilver unit. The stock driveshaft connects to a GM 12-bolt with Moser axles and an Auburn Pro Series carrier housing a Richmond 3.42:1 gear set.
Sure it's grimy but, hey, it's a 428!
The Suspension
The Firebird's front subframe uses Global West upper and factory lower tubular control arms with Del-A-Lum bushings to provide weight reduction, improved geometry and less deflection at the attaching points. QA1 coilover shocks with a firm 550 pound spring rate offer up increased adjustability for shock settings and ride height, and Superior Spindles 2-inch drop spindles ensure the suspension geometry isn't adversely affected by lowering the vehicle. A Hotchkis 1.125-inch front sway bar helps flatten out the curves. A 12.7:1 power steering box parted from a '90 T/A quickens turns-to-lock and increases road feel for comfortable back-road bashing.
With all that newer technology up front, the rear suspension had to keep pace. To that end, upgrades include Global West leaf springs with a 150 pound spring rate and Edelbrock IAS shocks. Chassis Works subframe connectors and Global West aluminum subframe bushings tie it all together and stiffen the chassis.