All-Aluminum 427 Street Stroker Testing

Working with the cam and heads, the intake manifold helps dictate the effective operating range of the motor as well. With plenty of head flow and our cam optimized for power production from 5,000 rpm to 7,000 rpm, we chose our intake manifold accordingly. Since the cam and heads were designed for power production higher in the rev range, we chose a single-plane intake manifold. The Edelbrock Super Victor seemed like a logical choice, but we didn't just install it out of the box and call it good. The intake was sent to the flow experts at Wilson Manifolds for custom porting work. The intake flow was optimized and the ports matched to the same 1262R intake gaskets used to size the entry of the head ports. In the interest of streetability (actually more due to the fact that the author forgot to secure a larger carb), the Wilson-ported Super Victor was topped off with a Holley 750 Street HP carburetor. A larger carb would certainly offer more peak power (we saw nearly 2 inches of vacuum present with the 750 Street HP), but we ran what we had. As the name would suggest, the Street HP Holley was actually a great choice for street use. The HP series is the standard of the industry for any performance carburetor, offering both impressive airflow and the tuning to back it up. The combination of the Wilson-ported Super Victor and Street HP-series Holley made for one serious induction system.

Naturally there were still a few odds and ends left to complete the motor. The ignition system consisted of an MSD billet distributor with matching cap, rotor, and plug wires. The 427 was run on the dyno using an MSD 6AL ignition amplifier and Denso Irridium spark plugs. The oiling system included a pan, pick up, and windage tray from Milodon, along with a high-volume oil pump and hardened oil-pump shaft. Additional features included a double-roller timing chain, 1.6 ratio Gold roller rockers from Comp Cams along with Hi Tech hardened pushrods. ARP supplied the 1/2-inch head studs, 7/16 rocker studs, and accessory bolt kit, while Fel Pro MLS head gaskets were employed to ensure adequate sealing. All testing was performed at Advance Product Engineering in Palmdale, California. The motor was primed and subjected to a computer-controlled break-in procedure using Lucas conventional oil, but we swapped over to the 5W-20 synthetic for all of the power runs. With jetting (75/80) and ignition timing optimized (35 degrees), the all-aluminum 427 stroker pumped out 615 hp and 545 lb-ft of torque. Best of all, the big-inch Windsor offered more than 500 lb-ft of torque from 3,850 rpm to 6,350 rpm, making for one sweet-for-the-street torque curve. Precious Metal was now ready to go in the engine bay-though we couldn't help but wonder how this motor might respond to a little boost? Maybe just one more dyno session is in order before we install this baby!