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Pontiac 421

Pontiac 421

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
6114-4150 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.150 inch bore Pin Dia.: 0.98 6114-4150 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.150 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
433 Pontiac Early and Late, FX, Comp Height: 1.585, -14cc Dish Top, PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-11.45, 87cc-9.08, 124cc-7.04 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6114-4160 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.160 inch bore Pin Dia.: 0.98 6114-4160 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.160 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
435 Pontiac Early and Late, FX, Comp Height: 1.585, -14cc Dish Top, PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-11.5, 87cc-9.1, 124cc-7.07 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6112-4150 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.150 inch bore Pin Dia.: 0.98 6112-4150 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.150 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
433 Pontiac Early and Late, FX, Comp Height: 1.585, -7cc Flat Top , PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-12.39, 87cc-9.62, 124cc-7.35 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6112-4120 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.120 inch bore Pin Dia.: 0.98 6112-4120 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.120 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
427 Pontiac Early and Late, FX, Comp Height: 1.585, -7cc Flat Top , PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-12.26, 87cc-9.51, 124cc-7.26 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6114-4120 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.120 inch bore Pin Dia.: 0.98 6114-4120 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.120 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
427 Pontiac Early and Late, FX, Comp Height: 1.585, -14cc Dish Top, PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-11.32, 87cc-8.97, 124cc-6.96 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6112-4180 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.180 inch bore Pin Dia.: 0.98 6112-4180 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.180 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
439 Pontiac Early and Late, FX, Comp Height: 1.585, -7cc Flat Top , PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-12.53, 87cc-9.74, 124cc-7.43 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6112-4160 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.160 inch bore Pin Dia.: 0.98 6112-4160 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.160 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
435 Pontiac Early and Late, FX, Comp Height: 1.585, -7cc Flat Top , PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-12.45, 87cc-9.66, 124cc-7.37 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6112-4125 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.125 inch bore Pin Dia.: 0.98 6112-4125 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.125 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
428 Pontiac Early and Late, FX, Comp Height: 1.585, -7cc Flat Top , PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-12.29, 87cc-9.53, 124cc-7.27 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
Choose Options
6114-4180 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.180 inch bore Pin Dia.: 0.98 6114-4180 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.180 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
439 Pontiac Early and Late, FX, Comp Height: 1.585, -14cc Dish Top, PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-11.57, 87cc-9.18, 124cc-7.12 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6114-4125 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.125 inch bore Pin Dia.: 0.98 6114-4125 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.125 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
428 Pontiac Early and Late, FX, Comp Height: 1.585, -14cc Dish Top, PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-11.35, 87cc-8.99, 124cc-6.97 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6114-4094 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.094 inch bore Pin Dia.: 0.98 6114-4094 421 Pontiac Early and Late FX Series -14cc Dish Top Pontiac Early and Late Forged Piston Set 4.094 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
421 Pontiac Early and Late, FX, Comp Height: 1.585, -14cc Dish Top, PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-11.2, 87cc-8.87, 124cc-6.88 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
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6112-4094 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.094 inch bore Pin Dia.: 0.98 6112-4094 421 Pontiac Early and Late FX Series -7cc Flat Top Pontiac Early and Late Forged Piston Set 4.094 inch bore Pin Dia.: 0.98
from $749.95
from $749.95
421 Pontiac Early and Late, FX, Comp Height: 1.585, -7cc Flat Top , PIN: .98", Full-Floating or Press Fit, Ring Groove: 1.2/1.2/3MM, Stroke: 4.000", ROD: 6.625, Approx Comp Ratio: 62cc-12.1, 87cc-9.41, 124cc-7.18 Effective June 15th 2026, These Pontiac 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 1/16-1/16-3/16.
Choose Options