You are better off with the B20A or even a USDM A5 because the B21A1 have issues with the FRM sleeves. If you know what you are doing you can put the B20A head on the B21A1 bottom end because that will make it a 10:1. You will burn oil down the road due to the FRM issues with the 2.1 motor.. If you would like to search you can try to find a SiR II 3rd gen Accord motor.. Let me know if you need any help on this issue

3rd gen Accord stuff www.3geez.com
3rd gen Prelude stuff www.preludepower.com