I'm wondering the same thing. I also wonder what compatibilty there is between F20 DOHC and the H23A1 in terms of external parts. I'm building an H23A1 but using an F20A crank, rods and balance shafts, as well as .25 mm overbore H22 Type S pistons to make in effect a big bore F20A DOHC. Compression will be 11.6:1, the head has been ported, treated to a three angle valve job and stock cams will be using AEM cam gears. I'm going to have a crank scraper made for it, and I'm using a higher output H22 oil pump. There is plenty more to the build-up, and since I'll be swapping into my 1992 Accord, I'd like to know as much as possible about swapping and tuning it. Any info would be appreciated!