sounds like his CRX is the DX model - if so, the 1.5L engine in it has Dual Point Fuel Injection where your HF has Multi Point Fuel Injection - yes, you could swap his DX engine into your HF, but you would need to swap the intake manifold, engine wiring harness and distributor from your HF onto the DX engine - you would also need to swap your HF flywheel and clutch assembly onto the DX engine - other than that, it would be a direct swap