Key changes in high-performance diesel pistons

Key changes in high-performance diesel pistons

Written by Alfie Bilk September 8, 2014 Mentor, Ohio: Wiseco, the eminent high-performance piston maker established in 1941, is launching a new range of diesel pistons for Dodge Cummins, GM Duramax and Ford Power Stroke engines. Using technology that should make a significant impact in the diesel performance world, the first two piston designs are devoted to Cummins 5.9 liter 12- and 24-valve engines and GM Duramax power units. These will be followed by new designs for Cummins 6.7 liter as well as various Ford Power Stroke models. The chief concern with cast aluminum factory pistons on high-performance diesel engines generating 850 to 1,000hp in street trim, and higher in truck-pulling and diesel drag racing, is premature failure. Alternatively, the shortcoming in high-output diesel engines with standard forged aluminum pistons can be soft, short-lived ring grooves. Wiseco’s solution is Armor Plate™. To the pistons’ most highly stressed areas—chiefly to the bowl, pin bores and ring grooves—Armor Plate adds hardness. In addition, engine building costs are eased, particularly the balancing process, by maintaining piston weights close to those of the original equipment units. Just as impressive is how Wiseco set about creating these new designs, collaborating with specialists in high-level competition. Adept at extracting the utmost from current diesel technology, Wiseco coupled their insight with their own piston-making expertise, which triggered studies of injector patterns and advanced bowl designs. The studies also brought remarkable weight savings for engines with internally balanced crankshafts. Custom units distinguish themselves with weights in the low 600g range, resulting in 30 percent net loss in piston mass, which prolongs crankshaft life by reducing twisting forces....
First off-the-shelf asymmetrical pistons for LS high-performance engines:

First off-the-shelf asymmetrical pistons for LS high-performance engines:

By: Sam Logan Particularly effective on forced induction and longer stroke models JE, our largest indigenous racing piston maker, brought a fresh new presence to asymmetrical forged pistons when they began investigating their potential in race engines, particularly high performance forced-induction engines. As you’d expect piston side loads increase with boost pressure—they also increase with longer stroke crankshafts and even aftermarket camshafts. But JE’s asymmetrical piston with differing skirt sizes and off-set pin has presented several interesting solutions.     -Introduces less friction -Reduces piston weight -200 LS configurations in stock -Two-day delivery 95% of the time -Two-week delivery on custom items -Five-day on expedited custom items Irvine California: JE has pioneered a new range of asymmetrical pistons for GM LS engines. Available off-the-shelf, they are the first of their kind. Known as asymmetrical because their skirts are of noticeably different sizes—a thrust side and a non-thrust side that address disproportionate loads in the cylinder. Also, their piston pin is positioned slightly off center. Though designed to support high cylinder pressures in applications producing 1,500hp-plus, both forced induction and nitrous, they also operate happily in naturally aspirated LS engines. Beyond this the piston configuration promotes lightness, strength, and durability as its unique design enables material to be distributed in the areas exposed to higher stresses. The major skirt, which operates on the thrust side, combats the highest side loads. The lowest side loads, in contrast, are handled by the minor skirt, which is free of undue weight and friction. Further weight reductions are achieved with 106-gram piston pins. Measuring 2.250in long these compare favorably with the pins of traditional...