The cylinders were bored and honed .020-inch over stock, bringing the bore to 4.020 inches. Again, a fixture (a torque plate simulates a head bolted in place) is used in the process. Says Robert Jung, "When boring the cylinders, it's preferred that all of the bores are in alignment and the cylinders are 90 degrees to the crankshaft. A Chevy block is a 90-degree V-8, not an 89-degree block."
With the basic machine operations complete, the major components were selected. A Callies Performance Products aftermarket crankshaft was chosen. Stroked .020-inch over stock and coupled with the slightly larger bore-size, the small block increased to 355 ci.
Clevite Engine Parts engine bearings, a set of Crower 6.00-inch rods, and JE flat-top pistons were also selected. The off-the-shelf Edelbrock cylinder heads chosen were Victor 23 Degree aluminum items with stainless steel 2.080-inch intake and 1.60-inch exhaust valves, (70cc) combustion chambers and 10.0:1 compression ratio. The camshaft chosen for test one would be an Edelbrock Victor Jr. Sportsman 2V hydraulic roller mated to the Crane roller rockers (1.5 & 1.6 ratio), Crane valvesprings, retainers, and locks. Other items worth noting were an Edelbrock water pump and timing chain, ATI harmonic balancer, MSD ignition system Champion spark plugs, a Victor Jr. 2900-intake manifold, and matching 750-cfm carburetor with manual choke.
The Roberts emphatically stressed meticulous workmanship in every phase of construction. Every part was cleaned to perfection-rotating parts were balanced and specifications checked again and again. Bobby Meeks remembers his first days of working with Vic Edelbrock Sr.: "Vic Sr's golden rule was to clean every part perfectly. Then measure and check every step of assembly. If you missed one item on our checklist, he'd jump all over you."
With the engine assembled, the first goal of the project had been accomplished. In this initial phase all selected parts were available from off the shelf or out of catalogs-no tricks and no secret parts were allowed. The engine was placed on the Edelbrock's dynamometer and assigned to senior test operator Curt Hooker.
Curt Hooker conducted each run, with Meeks, Joehnck and Jung making changes and fine-tuning the engine in between. Test one was performed on January 30, 1998 at 11:08 in the morning. Seven runs were made, with the best reading producing 503.8 CBHP (Corrected Brake Horsepower) at 6,448 rpm and 410.4 lb-ft of torque. Not the original 600 hp goal-but very good.
Several days later, the engine was run again with a Victor Jr. manifold with a one-inch open spacer, a set of 1.875-inch diameter headers, an 850-cfm carburetor, and a different tune-up. Over 500 hp was achieved with the second setup during seven dyno runs. Readings of 502.4 hp and 509.5 hp at 6,447 rpm with 415.1 lb-ft of torque were recorded. Test series three featured a slightly different Victor Jr. intake manifold (PN 2925) that was also a taller manifold with a different runner design. The best run produced a 514hp reading at 6,447 rpm with 418.8 lb-ft of torque.
For test four, the Edelbrock aluminum heads were milled, reducing the combustion chamber size to 60 cc and raising the compression ratio to 10.6:1. The seven runs in the test four sequence produced three readings over 500 hp, with the highest reading topping 529 hp (529.8) with 431.7 lb-ft of torque.
Major changes were made for test five. An Isky Racing Cams camshaft (PN 201581) was installed and the intake manifold was again exchanged for an Edelbrock Victor Ram I Tunnel Ram with two Holley 660-cfm carburetors. Results improved with three of seven pulls over 500 hp. The highest of the three was a 557hp reading at 6,942 rpm producing 421.7 lb-ft of torque.