Page 4 of Sport Pistons Compact Catalog by JE Pistons

DOME HEIGHT PISTON DECK STD OIL DRAIN BACK SPLIT OIL DRAIN BACK SIDE RELIEF (FOR FULL ROUND PISTONS) WRIST PIN HOLE/ PIN DIAMETER LOCK GROOVE PICK LOCK GROOVE (AVAILABLE FOR WIRE LOCKS) VALVE RELIEF TOP LAND TOP RING GROOVE 2ND LAND 2ND RING GROOVE 3RD LAND OIL RING GROOVE FORCED PIN OILER (CENTERED OR SPLIT) SINGLE OR DOUBLE SKIRT BOTTOM BAND TANG SLIPPER AREA (COUNTER WEIGHT CLEARANCE) VALVE LOCATION TERMINOLOGY Centerline Out is measured to where a 90o valve relief cutter would meet the deck to the piston center line EXH. VALVE STOP EXHAUST CENTERLINE OUT EXHAUST VALVE RELIEF INTAKE VALVE RELIEF INTAKE CENTERLINE OUT INTAKE VALVE STOP PINCL COMPRESSION HEIGHT/ DISTANCE VALVE POCKET DEPTH MEASURED VERTICALLY FROM THE PISTON DECK TO THE DEEPEST PART OF THE VALVE RELIEF RADIUS VALVE ANGLE GAGE POINT .500�h STD (.275 WHEN SPECIFIED) PISTON TO WALL CLEARANCE 4032 ALLOY PISTONS Bore Range Min. Clearance Sport Compact 2.500 to 3.625 .0022 to .0028 Sport Compact 3.626 to 3.999 .0025 to .0035 4032 ADDITIONAL CLEARANCE GUIDE LINES Drag Race +.0010 .0020 Turbo/Nitrous +.0005 .0010 Road Race +.0005 .0010 2618 ALLOY PISTONS Bore Range Min. Clearance Sport Compact 2.500 3.625 .0025 .0035 Sport Compact 3.626 3.999 .0030 .0040 2618 ADDITIONAL CLEARANCE GUIDE LINES Drag Race +.0010 .0020 Forced Induction/Nitrous +.0015 .0025 Road Race +.0015 .0020 Filled block +.0015 .0025 COMPRESSION HEIGHT 8.347 8.347 CRANKCL 3.437 1.7185 1.7185 5.433 5.433 .020 0.020 1.175 1.175 EXAMPLE: BLOCK HEIGHT 1/2 STROKE ROD LENGTH BLOCK DECK CLEARANCE COMPRESSION HEIGHT/DISTANCE JE designs are speci cally engineered for extreme applications up to, and including, professional competition. In this environment, the higher compression ratios, highest boost or heavy nitrous usage necessitate the higher tensile strength 2618 aluminum alloy, other features are listed below. Application speci c forgings for an optimized, uniform crown thickness Contact reduction groove to minimize frictional drag Accumulator groove for increased top ring stability and sealing CNC-machined side relief with lower support band for additional skirt strength Honed pin bores, double pressure fed pin oilers wire locks included PHYSICAL PROPERTIES OF 2618 Nominal Density 2.81 g/cc .100 lb/in3 MECHANICAL PROPERTIES OF 2618 Tensile Strength, Ultimate 440 MPa 64,000 psi Tensile Strength, Yield 370 MPa 54,000 psi Modulus of Elasticity 74 GPa 10,400 psi Fatigue Endurance Limit 125 MPa 18,000 psi SRP Pistons are designed for street/strip applications utilizing many compression ratio combinations compatible with pump gas as well as moderate turbo boost and nitrous oxide. SRP sport compact pistons are forged from 4032 low-expansion aluminum alloy for smooth and quiet operation. Honed pin bores with single, pressure fed pin oiler More economical because of forged side reliefs (reduces machining time) and thicker ring lands to accommodate a wider variety of applications Double Spiro locks included PHYSICAL PROPERTIES OF 4032 Nominal Density 2.68 g/cc .097 lb/in3 MECHANICAL PROPERTIES OF 4032 Tensile Strength, Ultimate 380 MPa 55,000 psi Tensile Strength, Yield 315 MPa 46,000 psi Modulus of Elasticity 79 GPa 11,400 psi Fatigue Endurance Limit 110 MPa 16,000 psi COEFFICIENT OF THERMAL EXPANSION FOR 2618 Temperature Range Average Coef cient oC oF ��m/m K ��in/in oF -50 to 20 -58 to 68 20.6 11.4 20 to 100 68 to 212 22.3 12.4 20 to 200 68 to 392 23.2 12.9 20 to 300 68 to 572 24.1 13.4 COEFFICIENT OF THERMAL EXPANSION 2618 aluminum expands approximately 15% more than 4032 aluminum, thus the 2618�fs initial piston-to-wall clearance has to be 15% This difference is most noticeable during a cold engine start. When cold, the 2618 piston can rock back and forth producing a slight the aluminum expands. Both types of aluminum have approximately the same clearances once the pistons have expanded and the engine running at operating temperatures. COEFFICIENT OF THERMAL EXPANSION FOR 4032 Temperature Range Average Coef cient oC oF ��m/m K ��in/in oF -50 to 20 -58 to 68 18.0 10.0 20 to 100 68 to 212 19.5 10.8 20 to 200 68 to 392 20.2 11.2 20 to 300 68 to 572 21.0 11.7 PISTONTERMINOLOGY JEVS.SRP 6 7

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