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Jeep 4.0

STEP 1: Choose Cyl Bore Size Show all STEP 1: Choose Cyl Bore Size
STEP 2: Piston Series Show all STEP 2: Piston Series
STEP 3: Connecting Rod Length Show all STEP 3: Connecting Rod Length
STEP 4: Piston Pin Diameter Show all STEP 4: Piston Pin Diameter
STEP 6: Top - Comp. Ratio Show all STEP 6: Top - Comp. Ratio
Compression Height Show all Compression Height
Crankshaft Stroke Show all Crankshaft Stroke
6650-3875 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.875 inch bore Pin Dia.: 0.931 6650-3875 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.875 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
243 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -10cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.53, 55cc-10.12, 58cc-9.77 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6650-3905 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.905 inch bore Pin Dia.: 0.931 6650-3905 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.905 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
247 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -10cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.66, 55cc-10.25, 58cc-9.89 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6650-3915 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.915 inch bore Pin Dia.: 0.931 6650-3915 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.915 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
248 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -10cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.7, 55cc-10.29, 58cc-9.93 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6650-3935 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.935 inch bore Pin Dia.: 0.931 6650-3935 4.0 AMC/Jeep 6 Cyl. FX Series -10cc Dish Top No Notch Jeep Forged Piston Set 3.935 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
251 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -10cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.8, 55cc-10.4, 58cc-10.02 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6652-3875 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.875 inch bore Pin Dia.: 0.931 6652-3875 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.875 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
243 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -15cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-9.88, 55cc-9.54, 58cc-9.22 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6652-3905 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.905 inch bore Pin Dia.: 0.931 6652-3905 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.905 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
247 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -15cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.01, 55cc-9.67, 58cc-9.35 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6652-3915 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.915 inch bore Pin Dia.: 0.931 6652-3915 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.915 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
248 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -15cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.04, 55cc-9.7, 58cc-9.37 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6652-3935 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.935 inch bore Pin Dia.: 0.931 6652-3935 4.0 AMC/Jeep 6 Cyl. FX Series -15cc Dish Top No Notch Jeep Forged Piston Set 3.935 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
251 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -15cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-10.15, 55cc-9.79, 58cc-9.47 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6653-3875 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.875 inch bore Pin Dia.: 0.931 6653-3875 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.875 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
243 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -21cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-9.22, 55cc-8.93, 58cc-8.66 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6653-3905 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.905 inch bore Pin Dia.: 0.931 6653-3905 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.905 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
247 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -21cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-9.35, 55cc-9.04, 58cc-8.77 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6653-3915 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.915 inch bore Pin Dia.: 0.931 6653-3915 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.915 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
248 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -21cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-9.37, 55cc-9.07, 58cc-8.8 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
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6653-3935 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.935 inch bore Pin Dia.: 0.931 6653-3935 4.0 AMC/Jeep 6 Cyl. FX Series -21cc Dish Top No Notch Jeep Forged Piston Set 3.935 inch bore Pin Dia.: 0.931
from $679.95
from $679.95
251 AMC/Jeep 6 Cyl., FX, Comp Height: 1.592, -21cc Dish Top No Notch, PIN: .931", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 3.440", ROD: 6.125, Approx Comp Ratio: 52cc-9.47, 55cc-9.17, 58cc-8.88 Effective June 15th 2026, These 6 Cyl Jeep ring grooves have been updated to the new specifications of 1.2-1.2-3mm. Parts manufactured prior to this date feature ring grooves with dimensions of 1.5-1.5-4MM.
Choose Options