Diamond Pistons Competition Series for 2020-2022 F-350 SUPER DUTY, F-250 2021-2022 E-350 DUTY - 30921-R1-8 and Rings, Forged Aluminum, 4.230 in. Bore, 3.976 in. Stroke, Compression Ratio 10:1, +25.50cc Head Volume, Ford, Godzilla, 7.3L, Set
Diamond Pistons Competition Series for 2020-2022 F-350 SUPER DUTY, F-250 2021-2022 E-350 DUTY - 30921-R1-8 and Rings, Forged Aluminum, 4.230 in. Bore, 3.976 in. Stroke, Compression Ratio 10:1, +25.50cc Head Volume, Ford, Godzilla, 7.3L, Set
A$3,195.38
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Description
Data: v2 - Desc: v4.2 - Upd: 2026-11-07 19:54:52
Features
Note for Pistons, Rings, Rotors, Rods and engine internals
Unless otherwise specified, some brands supply brake rotors, pistons, strut mounts, rods and rings separately. In some cases, titles may indicate plural, or 'set' - eg the term “ring set” often refers to the rings for a single piston only. If you’re unsure about what’s included with this product, please contact our team for clarification.
(keyword: pistons)Images are supplied by the manufacturer and may be generic. While all efforts are made to provide accurate pictures, there may be differences in the actual product, such as colour, quantity, version, or included components. Please carefully review the description and specifications for details on inclusions or any variations. Some items may be sold individually or in sets, and images may occasionally depict additional products or quantities not included in your purchase. For assistance or clarification, please contact customer support.
Specifications
Reference Information
| Reference Data (Provide these details to our support team) | |
|---|---|
| Brand Name/s | Diamond Pistons, Diamond Racing Products |
| StreetFX SKU | dpp30921-R1-8 |
| SFX Item ID | 5525861 |
| Accounting SKU | dpp-30921-R1-8 |
| Manufacturer SKU | 30921-R1-8 |
| Manufacturer UPC | 193564437297 |
| Alternative References | 30921-R1-8, DPP-30921-R1-8 |
Pistons and Rings, Forged Aluminum, 4.230 in. Bore, 3.976 in. Stroke, Compression Ratio 10:1, +25.50cc Head Volume, Ford, Godzilla, 7.3L, Set of 8
Diamond Pistons Competition Series pistons are for those looking to take their engine to a whole new level of power. These forged aluminum pistons are superior in strength and provide extra protection during the high-stresses of high-compression, forced induction, or nitrous.
Diamond Pistons Competition Series features:
• 3D milling on piston crowns for "ready-to-install" finish
• Generous valve pockets designed to work with stock or oversized valves and various cylinder heads
• Constructed from forged 4032 or 2618 aluminum alloy (where specified)
• Premium 8620 or H-13 steel wrist pins (where specified)
| Product Attributes | |
|---|---|
| Brand | Diamond Pistons |
| Manufacturer's Part Number | 30921-R1-8 |
| Part Type | Pistons |
| Product Line | Diamond Pistons Competition Series Pistons |
| UPC | 193564437297 |
| Piston Rings Included | Yes |
| Bore (in.) | 4.230 in. |
| Bore (mm) | 107.442mm |
| Stroke | 3.976 in. |
| Engine Stroke Type | Stock |
| Actual Engine Displacement | 7.3L/447 |
| Rod Length | 6.318 in. |
| Piston Style | Dish, with two valve reliefs |
| Piston Material | Forged aluminum |
| Compression Height (in.) | 1.320 in. |
| Piston Head Volume (cc) | +25.50cc |
| Wrist Pin Style | Floating |
| Wrist Pin Retainers Included | Yes |
| Wrist Pin Included | Yes |
| Pin Diameter (in.) | 0.990 in. |
| Piston Ring Thickness | 0.043 in. x 0.043 in. x 3.00mm |
| File Fit | Yes |
| Gapless | No |
| Top Ring Thickness | 0.043 in. |
| Top Ring Material | Ductile iron |
| Top Ring Facing Material | Plasma-moly |
| Second Ring Thickness | 0.043 in. |
| Second Ring Material | Ductile iron |
| Second Ring Facing Material | Ductile iron |
| Oil Ring Thickness | 3.0mm |
| Oil Ring Material | Stainless steel |
| Remanufactured | No |
| Quantity | Sold as a set of 8. |
| Notes | Approximate compression ratio 10:1. |
Compatibility
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