In our initial Big Ford Horsepower post, we told you how Trick Flow Specialties in Akron, OH was building a 598 big block Ford to out-power the 1,013-horse 565 cubic-inch Chevy it had assembled the prior year. In that initial post, we covered the short block assembly and showed you how most of the parts were off the shelf, meaning virtually anyone can duplicate the build with parts from suppliers like Summit Racing Equipment.
With the foundation for the 598 big block Ford prepared, it’s time to install the top end of the engine—cylinder heads, valvetrain, and intake manifold—so all those cubic inches get all the air they need to make big horsepower. We’ll also show you a couple of modifications needed to get everything to play nice together.
The Cylinder Heads
The PowerPort A460 360 cylinder head is designed for engines with a minimum bore of 4.500 inches (stock is 4.3600 inches). This is a great head for high-compression, normally aspirated engines like our 598, or for engines with a power adder like a multi-stage nitrous system or a big Roots-style supercharger.
The PowerPort 360s feature:
• CNC-profiled 87cc combustion chambers with 2.400 inch intake/1.880 inch exhaust valves
• 360cc intake/180cc exhaust runners with Trick Flow’s CNC Competition Port job. This is Trick Flow’s top-of-the-line port work with a high-resolution surface finish for maximum airflow. The ports are raised for better airflow
• Trick Flow Track Max® Pacaloy™1.645 inch diameter triple valve springs, rated to handle up to .850 inches of valve lift
As tested on Trick Flow’s Superflow bench, peak airflow is 453 cfm intake/321 cfm exhaust at .800 inches of valve lift. But it’s the mid-lift figures that really show how good the PowerPort 360 is—369 cfm intake at .500 inches of lift and 410 cfm at .600 inches.
The Other Parts
Jesel Pro-Series Shaft Rocker Arms: Designed specifically for the PowerPort A460 cylinder heads, the 1.8 ratio Pro Series rockers are made from Jesel’s 7000 Series aluminum alloy. That allows Jesel to make a rocker arm that’s stronger, lighter, and more than 19 percent stiffer than a comparable Jesel Sportsman rocker.
Crane Ultra-Pro Mechanical Roller Lifters: Among the strongest roller lifters available, the Ultra-Pros are also very lightweight to reduce valvetrain weight and increase rpm potential. The lifters have a “four-column” design to improve torsional rigidity, reinforced pushrod seats, and micro-polished roller wheels.
Trick Flow Chromoly Pushrods: Made from 4130 chromoly steel, these one-piece pushrods are heat-treated for use with guideplates. Trick Flow closes off the tips, then drills and chamfers the oiling holes to .093 inch. That prevents stress fractures and cracks.
Trick Flow R-Series A460 Intake Manifold: Intended for 500-plus inch, high-rpm engines, the Trick Flow® R-Series A460 single plane intake manifold features a one-piece, spider-type design with high-flow, individual extended runners and a raised plenum floor. It’s designed for use exclusively with the PowerPort A460 cylinder heads.
Moroso Drag Race Oil Pan: This nine-quart pan is designed for tube-chassis cars including dragsters, roadsters, and doorslammers. The fabricated steel pan has a full-length sump and comes with a solid-louvered windage tray. It clears cranks up to 4.75 inch stroke (with aluminum rods). Trick Flow modified the pan for use with an external oil pump.
In the next and final installment of our 598 Ford build, we’ll be fabricating a front motor plate and installing the Holley Dominator carburetor, MSD distributor, and front accessories (oil pump, crank trigger, balancer, and water pump). Then for the funnest part of all—strapping the engine on Trick Flow’s dyno and seeing how much power we can extract.