Lube to Live
The Edelbrock 460CJ heads feature a stock-sized intake port with large 2.19/1.76-inch valves and a 95cc combustion chamber. The heads also require roller rockers that are identical to a Cleveland Ford/Boss 302.
According to JGM, if the 429/460 has a weakness, it is the oiling system. For a low-rpm torque twister, the system works well. But for higher engine speeds where the horsepower lives, there are a couple of things that need addressing. Ford chose to lube the mains through the lifter galley, which means that the oil must pass through the lifters on its way to the mains and rods. This path is full of restrictions, which both reduces pressure and aerates the oil.
Much like the 351 Cleveland engines, the solution is to radically increase oil pressure to the tune of 70 psi. The higher pressure reduces foaming and ensures oil will make it all the way from the front-mounted oil pump back to the rear main. If oil starvation occurs, the rear main and rods will suffer the most. The solution requires a high-volume/high-pressure pump as well as a strong oil-pump driveshaft. JGM also recommends a solid distributor-gear drive pin (like an industrial rivet) instead of the hollow roll pin, because the stock pin shears off trying to drive the higher pressures. This pressure also demands a race-style filter to prevent bursting. Of course, this also means being very careful when the engine is cold to limit pressure-induced filter explosions when the oil is more viscous.
CC's 466
We also bolted on an Edelbrock Performer Air Gap 460 intake to our completed engine package along with a 750-cfm Holley carburetor with an HP main body to feed this 466ci thumper. Between the aluminum heads and intake, we managed to lipo almost 100 pounds of ugly iron off this beast.
After dredging a complete 460 out of a '73 Lincoln Continental, we dissected it and delivered the block, crank, and rods to JGM. To create a solid foundation, we decided on also investing in a good short-block with a set of Federal-Mogul forged Speed-Pro flat-top pistons in case we decided to squeeze a little nitrous in the future. These pistons also gave us a pump-gas-friendly compression ratio when paired with the 95cc-chamber Edelbrock heads. Grubbs then supplied a set of rebuilt truck rods using ARP bolts to add a measure of durability. JGM also bored and torque-plate honed the block and oversaw machining our crank down 0.010-under to work with the Federal-Mogul bearings.
JGM has built a healthy 466 (see the Project 642 dyno chart) with completely ported iron production heads, but Grubbs reports that unless you enjoy a challenge, the effort really doesn't pay off in terms of the investment versus the ultimate power gain. We decided on a set of Edelbrock aluminum Performer RPM heads and a Performer RPM Air Gap intake as our route to power. These heads are intended to use roller rockers, so we plugged in a set of Harland Sharp 1.73:1 rockers to help with valve lift. This brought us to cam selection, and it just seemed a good idea to go with Edelbrock's entire Performer RPM package that uses a streetable flat-tappet hydraulic camshaft (see Cam Specs sidebar).
JGM then assembled the 460 with its recommended oiling-system changes and bolted the engine to the dyno. We also included a Holley 750-cfm mechanical-secondary carburetor with the HP body conversion (see that story elsewhere in this issue) to act as mix-master while also including a set of Hooker 131/44-inch chassis headers. This test was performed on Grubbs' own SuperFlow 901 engine dyno, but the cell does not leave room for a complete exhaust system. We also decided to test both Edelbrock hydraulic cams. The Performer-Plus cam is designed for torque while the RPM cam offers more duration and lift for a major horsepower boost.
The Performer cam made some awesome torque with 523 lb-ft, but that same short cam timing only managed 406 hp. This spurred the JGM crew to swap in the larger RPM cam to which the 466 responded with a pump-gas-fed 503 peak horsepower at a mere 5,200 rpm while shaking the floor with 555 lb-ft of torque at 4,200 rpm. These numbers are actually very close to Edelbrock's power claims for their Performer RPM package. Even in a 4,000-pound car, this is good enough for low 12s to high 11s depending on the weather and altitude. This motor was incredibly easy to assemble and required no custom parts. Do it yourself in your garage. Bolt it in your favorite Ford and you've got a tire-roaster.