6146-4180 400 - 4.375 Stroke Pontiac Late FX Series -22cc Dish Top Pontiac Late Forged Piston Set 4.180 inch bore Pin Dia.: 0.99" Comp Height: 1.222" Piston Ring Kit Option:Pistons - Pins and Locs Without Rings 23 NOTE: Most FE‑series OEM

23 NOTE: Most FE‑series OEM connecting rods require narrowing at the pin end to achieve proper side clearance within the 2

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6146-4180 400 - 4.375 Stroke Pontiac Late FX Series -22cc Dish Top Pontiac Late Forged Piston Set 4.180 inch bore Pin Dia.: 0.99" Comp Height: 1.222" Piston Ring Kit Option:Pistons - Pins and Locs Without Rings 23 NOTE: Most FE‑series OEM480 Pontiac Late , FX, Comp Height: 1. 222, 22cc Dish Top, PIN: . 99", Full Floating or Press Fit, Ring Groove: 1. 2 1. 2 3MM, Stroke: 4. 375", ROD: 6. 8, Approx Comp Ratio: 62cc 11. 58, 87cc 9. 33, 124cc 7. 34 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.