Richard Holdener
October 1, 2009
Before leaving the wrecking yard with our new fuelie motor, we took the liberty of swapping out the stock TFI distributor for its carbureted equivalent.

With a little horse trading, we were able to secure not only a used Holley carb, but also managed to have the Pro Comp heads surfaced in exchange for the complete EFI system. The owner of our machine shop was in need of a stock 5.0L EFI system for a customer and had a used Holley 750 double-pumper in his shop, just looking for a new home. We surfaced the Pro Comp heads to bring down the chamber size from 64 cc to just 60 cc. This bumped the static compression ratio of the 302 by roughly 0.5 point. For gaskets, we again turned to Pro Comp, which offers a complete set for $25.

The heads were installed using the stock head bolts. Next came the new, hardened pushrods and Pro Comp roller tip rockers. For about $50 more, we could get a set of true roller rockers, but we were budget minded on this motor and opted for the roller tip rockers instead. Running the stock stamped-steel rockers on the Pro Comp heads was not an option, as the bolt-down rockers would not work with the rocker studs supplied with the heads. Besides, we hated the idea of running stock rockers on a performance motor. We then installed the Funnel Web intake, followed by our used Holley 750 carb. Planning ahead in the wrecking yard provided the necessary distributor, which we used with the stock plug wires (ours were in decent shape after a quick cleaning).

The final step was to bolt on a set of 1 3/4-inch Hooker Super Comp headers (not included in the buildup cost) and Down-Low 5.0 was ready for some dyno action. The final bill for all the madness was $1,064 after trading the EFI system for the Holley carb and surfacing. If we had to purchase a new Holley carburetor, figure on another $275 for a 750-cfm vacuum secondary model. Even if we had to spend the extra $275 for a new carb, that is still chump change for a complete aluminum-headed performance 5.0L!

Induction chores are handled by a single-plane Funnel Web intake manifold. Designed to shift the torque curve, the Funnel Web sacrifices low-speed torque for high-rpm power. In truth, a dual-plane intake would be a better match for street use on this combination, but we were determined to make 400 hp.

The rings and bearings had long since been acquainted, but the same could not be said for the new cam and roller lifters. Given the roller profile, a break-in procedure was not mandatory, but we elected to give all the new components time to get properly acquainted before letting the hammer fly. The oil pressure looked steady at 55 psi, and the motor sounded plenty healthy breathing through the 3-inch dyno exhaust.

The initial pulls showed plenty of promise, with Down-Low pumping out more than 300 lb-ft of torque at 3,000 rpm. We experimented with timing (eventually settling on 35 degrees) and minor jetting to the used Holley before letting the hero pull. With a safe air/fuel mixture in the high 12s, the 302 eventually pumped out 399 hp at 6,000 rpm and 363 lb-ft of torque at 5,200 rpm.

The single-plane intake meant power production was kept higher in the rev range (a torque peak of 5,200 rpm is pretty high), but the little 302 did manage to exceed 350 lb-ft from 4,600 to 6,000 rpm. In hind sight, a dual-plane would likely be a better choice for a street-driven 302, but we wanted the big number and only wanted to spend a grand doing it. In the end, we made 399 hp for $1,064. If that doesn't qualify as a Down-Low 5.0, we don't know what does.