Hardcore LS: LME’s 700-Horsepower LS Engine (Part 1)

Machine work included cutting 0.010 inches off the deck. However, you’d be hard-pressed to take the same mill, wring it out for all it’s got during an open-track event or test and tune night at the local dragstrip and then rely on the same engine to get you home time after time. These requirements weren’t what the normal crowd was after.

The custom-grind COMP Cams camshaft allows the big-inch LS engine to breath in all areas of the rpm. This means lots of low-end grunt to pull the vehicle out of corners and plenty of high-horsepower up top in the rpm range.

With the help of the LME staff, the Chevy Hardcore guys applied some camshaft lube liberally and carefully installed the ‘stick, being especially careful not to gall the camshaft bearings. Chevy Hardcore opted for short travel hydraulic race lifters (Ti-bar required for LS blocks). What’s so special about these lifters? Well, they have been engineered from a patent-pending design that specifically performs at higher engine speeds. They are designed to limit the lifter’s internal piston as it is pumped up. By limiting that movement, the COMP Cams short travel race hydraulic roller lifters cut down on the loss of power and limit valvetrain failure at higher rpm.

The Clevite H-Series bearing set came complete with main and rod bearings. Rod journals are large, too, with 2.100 inches of diameter, able to support a minimum rod length of 6.125 inches. Before the crank was planted, the H-Series Clevite main bearings were installed. H-Series bearings for this application are important considering the potentially mid- to high-rpm this engine will live at.

The 502-inch LS motor relies on a super-fortified forged crankshaft from Lunati. The Pro Series cranks feature aircraft-quality standards and drilled rod journals with lightening holes to reduce the inertia weight of the crankshaft.

Lunati Pro Series rods were used to handle the high-rpm activity. The rods feature aerospace 4340 alloy steel and come complete with ARP 2000 rod bolts. LME fitted the big end of each rod with a narrowed, Clevite (PN CB66HN) rod bearing.

The custom-built, 4.165-inch bore Wiseco pistons feature -19cc, reverse dome LS7 pockets and lateral gas ports were custom cut by Wiseco to handle the 11.5:1 squeeze in the bores. Each slug was also treated to an anti-friction coating on the skirts for extra strength and to wick away power-sapping heat. Of course, Bryan Neelen shared his method behind the madness. “As cubic inches increase, the total volume of the piston and combustion changer increases to maintain a certain cubic inch. For example, a 427ci engine with 68cc chambers will need a -6cc piston to make 11.5:1. For this 502 inches, we’d need a -19cc dished piston to maintain the same, 11.5:1 compression with 68cc chambers.” With plans to hit this engine hard with high-rpm blasts, the ring package was just as important to the remainder of the build.

Each forged piston was outfitted with Wiseco’s ArmorGlide skirt coating. The allows for superior lubrication to minimize friction, maximize horsepower, and provide improved wear resistance. It also allows for a better ring seal and reduced noise from piston knock in tighter clearance bores.

The Total Seal piston ring package consists of a Top AP Stainless Chrome, second cast Napier, and standard tension 3 mm oil rings (PN 001874). Why is the ring package selection so important? In a nut-shell, rings provide the vital seal between the combustion cycles and the oil. Rings also prevent blow-by and, more importantly, prevent the rings from butting up against one another and scoring the cylinder walls. A healthy set of rings is essential to generating and maintaining power.