It was a bright day for him when he fired and drove his car for the first time, about one year ago. Since then, he cruises it every weekend if the weather cooperates. His favorite stuff is autocross, open-track days, dyno events, and belonging to the Monterey Bay Trans-Am Racing Association. In the grand scheme of things, you might even call this car a sleeper. Standard Z/28 appearance and that knockout yellow, yes, but really nothing else externally that would reveal the car's true identity.
Meanwhile, John considers some mandatory upgrades, and when he's done with them, there will undoubtedly be many more. The immediate future calls for disc brakes in back, electrically driven fans for the engine, and moving the battery to the boot. While he's at it, maybe he'll investigate Gear Vendors' new Manual Transmission overdrive kit for the Muncie M21/M22 transmission or a straight five-speed conversion from Keisler or Tremec.
Regardless of the outcome, matching-number freaks can rest easy. John has tucked away virtually everything that originally came on the car. Then, one brilliant day before the overinflated musclecar craze collapses and an original, documented Z's worth, say, a half-mil, he can easily put it back 40 years, all the way to 1969.
Drivetrain
Small-block power it is, this time by Golen Racing Engines (Hudson, New Hampshire). Chad Golen did the machine work. He decked, bored, honed the block with torque plates, balanced, and blueprinted the assembly. He planted ARP main bearing studs and fasteners throughout. John could certainly have used internals costing a lot more, but for his intentions, they just weren't warranted. Chad filled the '70 350 four-bolt main cylinder block with an Eagle 3.750-inch 4340 forged stroker crank (383ci) that is companion to the Eagle 4340 H-beam rods. He fitted the SRP 11:1 forgings with Speed-Pro plasma-moly rings and full-floating wrist pins. Chad slipped on a Melling high-volume oil pump, pick-up, and HD drive and snuggled them away beneath a Canton 6-quart aluminum road-race sump.
Maybe the snap of that Comp Cams solid roller is what prompted H's exclamation. Duration at 0.050 inch is 248/254 degrees. Lift is 0.576 on the intakes, 0.532 on the exhausts. This is accompanied by more Comp equipment: hardened pushrods (and hardened guideplates) prod Pro Magnum 1.6:1 roller rockers that act on 2.02/1.60 valves. The Patriot Performance Gold Series valvesprings are atop the Patriot 225cc CNC-ported aluminum cylinder heads holding 68cc combustion chambers.
On the upside, an Edelbrock Victor Jr. topped by a Pro-Systems 750-cfm Blaster-Series carburetor that actually flows 840 cfm. Since the Z/28 was already equipped with the ZL2 cold-air cowl-induction hood, John sandwiched a K&N filter between it and stopped right there. Fuel is fired by an MSD Pro Billet distributor, Blaster coil, 6AL box, and Pro primary wires. Timing is 18 degrees at idle.
Hooker Super Competition headers feature 171/48-inch primaries and lead to custom QTR electrically operated dump tubes. While he was down there, Howard Cauntay at All-American Muffler (Salinas, California) also connected the sides of the engine with a custom X-pipe.
That Hurst-shifted Muncie M21 (close-ratio, 2.20:1 Low gear) is original equipment, but rebuilt with modern upgrades by Mike Stacks at Standard Transmission (Sand City, California). Torque is passed through a Centerforce Dual-Friction clutch assembly to the OE driveshaft and finally to the original 12-bolt axle. A Posi-traction differential with a 3.73:1 ring-and-pinion makes certain the rubber burns evenly.