In this Finite Element Analysis image, the highest stress levels are identified by the bright green areas, shown here on the piston crown. The colors start in a dark blue, signifying low stress, and increase as the colors change to green, yellow and red.

Introducing unconventional ring package

Above the piston pin lie the ring grooves that are machined to fit 1.2mm top, 1.5mm second and a 3mm oil control ring. Though not included in the piston package JE recommends using their Pro Seal ring pack. These packs include a carbon steel nitrided top ring, a Napier-style hooked face second ring, and a standard-tension oil control ring. Significantly, the top ring has a more durable ring face than the normal plasma moly inlay type and as a result is better suited to combating higher cylinder pressures induced by nitrous oxide and forced induction. The most interesting element of the second ring, a Napier-style hooked-face ring, is that it possesses superior oil control potential compared with the conventional tapered second ring. 

Also noteworthy, these new asymmetrical LS designs accommodate factory oiling squirter systems, which will continue to spray in the correct locations and keep the pistons cool. To further reduce the likelihood of hot spots and pre-ignition, JE adds smooth-finish crowns, a process that blends all the edges of the piston crown, including the valve reliefs. Though the intake and exhaust valve pockets act as a guide to the piston’s correct orientation, a laser engraved arrow marked “Front” points to the front of the engine to ensure the asymmetrical skirts are positioned correctly.