Diamond Forged Piston Kit — Chevrolet Gen V LT1 / LT4 — 4.000 in stroke
Diamond forged pistons for Chevrolet Gen V LT1 / LT4
Choose a 8-piston kit to suit your measured engine and planned rotating assembly. The selector identifies the catalogue bore, piston crown volume, nominal compression ratio where published, and supplied gudgeon-pin option.
Photo: representative Diamond piston catalogue image. Crown shape, valve reliefs, skirt finish and supplied components may differ by the selected part number. Use the kit specifications and option selectors to confirm your order.
Made to order and delivery
These pistons are supplied by BBT as special-order, made-to-order items. Allow approximately 5–6 weeks for delivery, pending Australian customs processing time. Supplier manufacturing schedules, international freight and customs clearance can extend the estimate. Contact BBT before ordering for a time-critical build.
Included components and build dimensions
2618 aluminium forged pistons, the listed ring set, gudgeon pins and retainers are included. The listed pin is already included in the selected kit; this listing does not add a separate pin-upgrade charge.
| Piston Quantity | 8 |
|---|---|
| Compression Height | 1.115 IN |
| Stroke | 4.000 IN |
| Rod Length | 6.125 IN |
| Ring Set Thickness | 1.50 MM x 1.50 MM x 3.00 MM |
| Forging Type | Inboard |
Kit selection
| Kit SKU | Bore | Crown volume | Ratio | Included pin | Ring set | Retainer | Oil-rail supports |
|---|---|---|---|---|---|---|---|
| 21607-RS-8 | 4.070 IN | -10.00 CC | 11.50:1 nominal | H9272250250C | 09054070 | 015111-16 | Yes |
Fitment and assembly
For Gen V direct-injection LT1/LT4 builds with the listed crank, rods and bore. Confirm your head, fuel-injection crown geometry and block/sleeve specification. Stroker kits require the matching crankshaft. Gen II LT1 engines use a different piston design.
Catalogue bores are finished cylinder-bore sizes. The finished compression ratio depends on chamber volume, deck clearance and compressed head-gasket thickness. Have your engine builder verify piston-to-wall clearance, ring gaps, pin fit and piston-to-valve clearance using the supplied Diamond instructions before machining or assembly.
BBT workshop support
Built by Boost & Tune can help select a specification for your fuel, boost and intended use. Machining, engine assembly, connecting rods and tuning are purchased separately.