PRO GUIDE
JE
M-8 Ultra Series Pistons
Cypress , California based JE Pistons is now offering Ultra Series pistons that have been developed specifically for M-8 engines . The ' secret sauce ', according to the company , is its proprietary ' Aligned Grain Flow ' technology . " Being one of the only fully integrated piston manufacturers in the USA , our in-house forging operation has allowed for the development of an improved forging process that maximizes the alignment of the aluminum ' s grain structure , which translates to ' next level ' tensile strength . " This enables the pistons to stand up to the extreme power the M-8 builds , of 400 hp or more , or simply offer extreme durability for milder builds . " Ultra Series pistons combine this foundational strength with performance and durability , enhancing features such as JE ' s Thermal Barrier crown coating , Tuff Skirt coating , antidetonation grooves , lateral gas ports , an accumulator groove , and more ." The ceramic-based Thermal Barrier crown coating protects the piston by reducing heat transfer , especially in high-heat environments like built M-8 engines . Piston ring provisions , including lateral gas ports and an accumulator groove , aid in maintaining consistent ring seal at the top compression ring , which is crucial to consistent power , especially when power multipliers like turbos get thrown into the mix . In addition to the ' Aligned Grain Flow ' material itself , the
' Aligned Grain Flow ' technology
forging design that JE uses for its M-8 engine Ultra Series pistons has been optimized with internal and external bracing - features not commonly seen in V-twin piston design . This helps mitigate piston flex under heavy engine loads , adding to the pistons ' strength qualities without adding unnecessary weight . Additional features include 3D under crown milling for additional weight savings , offset pins for reduced piston rock and skirt notches for optimal clearance at bottom dead center . They are now available in standard ( 4.250 "), 4.310 " (+. 060 ") and 4.320 " (+. 070 ") bore sizes ( 4.500 " stroke ), each with the option of a 10.25:1 or 11.25:1 compression ratio . They are supplied in kits including two pistons , rings , wrist pins and wire locks - all under the one part number .
JE PISTONS Cypress , California , USA Tel : 714 894 6650 www . jepistons . com
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