K20 K20Z1 Silicone Pre Fit Heater Hoses K Series K Swap EG EK DC2 Civic Si CRX
* These only fit with K20A/A2/A3 and Z1 engine or cylinder heads.
One end is made to fit the smaller heater core side and the other end is made slightly larger to fit the K-series engine side. The hoses are made with a thick high temp rated silicone and 3-ply for excellent reliability. If you want to keep the heater control valve installed, simply splice it in location on the hose leading to the cylinder head and you're done.