EF/HF and Swapping Info

can anyone tell me what HF is please i cant find it, i know ef is the japanese model name for the 4th gens but what is hf, and can anyone give me a rough estimate on how much it would cost to swap a d16a6 crx si for a b16a crx vt please? thanks alot for any info =)

The HF model is still an EF. HF just stands for "high fule".

And to do the swap it will cost your around $2000.