The PowerPort 360 heads feature 122cc combustion chambers with 2.300-inch intake and 1.880-inch exhaust valves and CNC bowl-blended valve seat transitions (left). The efficient, heart-shaped chambers were smoothed and blended, and treated a 50-degree angle valve job to reduce any obstructions to airflow moving smoothly into the cylinders.

The intake runners were modified as well. The original 360cc Fast As Cast runners (shown here) are an as-cast design that rival CNC-ported runners in flow rate.

The modified 365cc runners on the right have raised floors—essentially raising the ports by .150-inch—and mildly recontoured and smoothed walls to give incoming air and fuel a straighter shot at the valve.

The lifters are COM Cams’ Endure-X mechanical rollers. The big block Chrysler-sized .904-inch diameter lifters are stronger, more rigid, and lighter than many other lifter types. Just as important, the bigger lifters (stock big Chevy is .842 inches) have larger roller wheels and axles, plus larger ‘legs’ where the axle mounts. That last item is a big plus when you’re running really high spring pressure.

Engine builder Todd Hodges lowers the PowerPort head onto the block. The head studs are then torqued to 80 ft.-lbs. (with ARP lubricant). The head gaskets are Multi-Layer Steel (MLS) gaskets from Cometic. These gaskets are designed to withstand extreme cylinder pressures.

With the cylinder heads installed, Todd degrees the camshaft off of the valve spring. Speaking of valve springs, these are 1.645-inch diameter triples with 835 lbs. open/290 lbs. seat pressure.

The Jesel Sportsman shaft rocker arms use these stands that screw into the existing rocker arm stud holes. The intake rocker stand on the right (marked 3B) uses a shorter bolt than the exhaust rocker stand (marked 1A). It can get easy to mix them up in the heat of assembly, so be careful!

The rocker stand bolts are torqued to 60 ft.-lbs. (with 30 weight oil); the rocker shaft bolts are torqued to 26 ft.-lbs. (also with 30 weight oil). The rocker arms are adjusted by cylinder firing order. Once the rockers are set, the adjuster nuts are torqued to 25 ft.-lbs.

The Trick Flow R-Series intake manifold is designed specifically for 500-cubic-inch and larger engines. With high-flow, extended length runners and a raised plenum floor, the R-Series delivers significant power gains in the 3,500-8,000 rpm range. Trick Flow had to fill in the manifold floor and raise the roof to match the revised intake ports on the PowerPort heads.

Todd installs the Milodon high-volume oil pump and matching pickup.

He double-checks the clearance from the pump to the oil pan floor by measuring the distance from the pan rail to the top of the pump, then transferring that measurement to the pan. Minimum clearance should be ¼-inch; we had 3/8-inch.

The Milodon oil pan is lowered into place. The eight quart pan has a full-length louvered windage tray and double trap doors to keep oil flow controlled under hard acceleration. The pan also has a small kickout on the passenger side to help improve ground clearance.

One 565-cubic-inch big block Chevy, ready for its carburetor, ignition system, and accessories before heading to the dyno. Join us for the final installment of this series and find out what kind of horsepower the 2012 Summit Racing SuperSeries Top Class Champion will be getting!