It’s a little hard to see, but a .001 inch of material was removed from the inner corner of the block to gain a little extra clearance for the crank counterweight.

If—saints forbid—the valvetrain self-destructs, screens epoxied over the oil return holes in the lifter valley will help keep the big chunks out of the bottom of the engine.

Roller cam bearings, like these from Ford Racing, can handle high valve spring pressures better than plain bearings, and they help reduce power-robbing friction. These ultra-low-friction needle roller bearings require so little lubrication that you can actually block off the stock cam oiling holes. This reduces both oil aeration and power loss due to windage in crankcase.

The roller cam bearings get oil by old-fashioned splash lubrication from the crank. The cam bearing oil passages in the main journal saddles are fitted with restrictors to help keep more oil around the main bearings.

Main bearing clearance is checked with a dial bore gauge. The caps are torqued to 110 ft.-lbs. with the bearings installed. Recommended clearance for these Clevite H-Series bearings is .0030 to .0031 inch.

The Scat forged crank was balanced at Trick Flow’s facility. The copper-colored weights represent the weight of the piston/ring/connecting rod assemblies. The crank was pretty close to optimal out of the box, requiring just a 65 gram slug of Mallory metal in the front counterweight.

Rod bearing clearance is checked with a dial bore gauge; clearance with the Clevite coated bearings should be .0025 to .0027 inch. Rod bolt stretch was also checked and found to be within the .005 to .006 inch tolerance range.

Piston meets connecting rod. Wiseco designed a custom forged piston just for this build; it has a 6.8cc dome that matches up to the combustion chamber shape on Trick Flow’s PowerPort A460 cylinder heads. Wiseco also applied its ArmorGlide™ skirt coating to reduce friction. The 598 stroker combo uses 6.800 inch big block Chevy rods. Trick Flow sourced a set of Callies Compstar forged H-beams. Note the double spiral locks.

With clearances checked, bearings lubricated, and piston/rod sets assembled, it’s time for assembly. First up is the Scat crankshaft. Forged from 4340 steel, the internally balanced crank has lightening holes in all rod throws; large-radius journals improved strength and wear resistance. The ARP main studs are torqued to 110 ft.-lbs. and the splayed cap bolts to 100 ft.-lbs. (with ARP Ultra-Torque assembly lube).

Todd checks crank thrust (endplay) with a dial indicator. Acceptable endplay for a 460 is .004 to .008 inch; ours came in at .006 inch.

The piston/rod assemblies are slid into their bores. Rod bolts are torqued to 88 ft.-lbs. using CMD #3 assembly lube. Rod side clearance is checked with a feeler gauge; proper clearance is .027 inch.

The COMP Cams mechanical roller cam is a very big stick—duration is 285/300 degrees at .050 inch, and lift is .873/.831 inches (with a 1.8 ratio rocker arm). Lobe separation is 114 degrees.

Unlike timing chains and gear drives, a Jesel belt drive does not transfer the crankshaft (torsional) harmonics to the cam—harmonics that can cause cam timing to jump around. The Jesel belt drive is a “dry” system that requires no oil lubrication. It also allows up to eight degrees of cam adjustability (either advance or retard). The cam sprocket hub had to be machined .0004 inch to bring camshaft end play into proper specifications.

Camshaft endplay is checked and found to be within spec at .004 inch (the range is .002 to .006 inch). The Jesel drive has a removable cam cover that gives you access to the cam without having to disturb the front crank seal. The cam cover has a flexible seal that fits around the cam sprocket to keep the oil in.

The camshaft was degreed to the 110 degree intake center line recommended by COMP Cams (four degrees advanced). Our 598 short block is now ready for the top end, oiling system, induction, and ignition system.