CP Piston & Ring Set for Acura/Honda K24 w/K20A/A2/A3 - Bore (87mm) - Size (STD) - Compression Ratio - SC7045-4

The CP Piston & Ring Set for Acura/Honda K24 w/K20A/A2/A3 (SC7045-4) is a complete forged piston kit built for the popular K-series engine swap and stroker combination — pairing a K24 block with a K20A, K20A2, or K20A3 cylinder head. Machined to a standard 87mm bore, this set gives engine builders and swap enthusiasts a precision-fit replacement or upgrade for high-revving, naturally aspirated or forced-induction K-series builds.

Key Features & Benefits

• Complete kit — includes pistons, rings, pins, and locks in one set, simplifying parts sourcing for a K-series rebuild or head swap.
• 87mm standard bore — matches factory K24 bore specification, ideal for a stock-bore rebuild without the need for an overbore machining operation.
• Compatible with K20A/A2/A3 heads — engineered so compression ratio stays consistent whether you're running a K20 or K24 cylinder head, giving swap builders flexibility in head selection.
• CP Pistons construction — a trusted name among engine builders for precision-machined, high-performance forged pistons used in competition and street K-series applications.

Specifications

• Brand: CP Pistons
• MPN: SC7045-4
• SKU: CPPSC7045-4
• Bore Size: 87mm (STD)
• Set Type: Piston & ring set (full set of pistons, rings, pins, and locks)
• Application: Acura/Honda K24 block with K20A/A2/A3 cylinder head
• CARB Status: Not CARB legal — not for sale or use in California on pollution-controlled vehicles

Fitment

This piston and ring set is designed for Acura/Honda K24 engine blocks paired with a K20A, K20A2, or K20A3 cylinder head — a common configuration for K-series swaps and displacement builds. The 87mm standard bore matches factory K24 specification, making this set suited for a stock-bore rebuild or fresh short block build rather than an overbore/oversize application. If your build calls for an oversized bore (such as +0.5mm or +1.0mm), a different SC part number will be required — check with our team to confirm the correct spec for your combination before ordering. This product is not CARB legal and cannot be sold or installed on emissions-controlled vehicles in California.

What's in the Box

• Set of pistons (quantity to match a 4-cylinder K-series engine)
• Matching piston ring set
• Wrist pins
• Piston pin locks

Why Buy from ThreePiece.us

ThreePiece.us backs every order with expert fitment support to help confirm you're ordering the correct bore size and configuration for your specific K-series build before it ships. Every order ships free, and you can spread the cost of your engine build over time with 0% APR financing available through Affirm. Our team is available to answer application questions on forced-induction builds, stroker combinations, and head/block pairings before you commit to a purchase.

Frequently Asked Questions

Q: Will these pistons work with a K20A2 head on a K24 block?
A: Yes. This set is designed for K24 blocks paired with K20A, K20A2, or K20A3 cylinder heads, and compression ratio remains consistent across these head options.

Q: What's included in this piston set?
A: This is a full set including the pistons, matching piston rings, wrist pins, and pin locks — everything needed for the piston side of a short block rebuild.

Q: Is this bore size correct for a stock K24 rebuild?
A: This set uses a standard (STD) 87mm bore, matching factory K24 specification, making it appropriate for a stock-bore rebuild rather than a block that has been overbored.

Q: Can I use this piston set in California on an emissions-controlled vehicle?
A: No. This product is not CARB legal and is not for sale for use on pollution-controlled vehicles in California.