Honda K-Swap Complete Guide — K24 into Civic / CRX

The K-swap has been the benchmark Honda engine build for 20+ years. The K24A2 from the 2002–2006 Acura RSX Type-S makes 200 whp naturally aspirated, revs to 8,200 RPM, and responds brilliantly to cams, headers, and a good tune.

For most builds, the K24A2 (from the RSX Type-S) is the preferred core. It has the best flowing head of the K-series family. K24A (from Accord/Element) blocks are popular budget options — pair an Accord K24A block with a K20A2 head for the popular long-rod combo.

Mount selection is critical. Innovative Mounts and Hasport both offer quality EG/EK K-swap mount kits. Hasport mounts have a slight edge in noise isolation; Innovative mounts are slightly more budget-friendly.

Transmission: The K20Z3 6-speed from the Civic Si is the cleanest bolt-in option. The K20A2 transmission is also excellent. Avoid the K24A automatic.

ECU options: Hondata K-Pro is the gold standard — full engine management, data logging, launch control, and rev limiting. The KTuner is a more budget-friendly alternative that works very well for naturally aspirated builds.

Axles: Use Raxles or purpose-built K-swap axles. Do not try to make stock axles work.

For naturally aspirated builds, a 4-2-1 header paired with a proper KPro tune and K20A2 cams will get you to 220–230whp. Add ITBs for a full race-inspired setup.