I am looking into buying a '91 crx with the d15 in it. I just picked up an f22b1 motor with the tranny, and wiring harness for a whopping $70. The car itself is around $700 but I am going to try and talk him down. I am going to swap the f22b1 into the rex for the simple reason that I don't know many that have done it. I like swaps that are out there. I was wondering if anyone could give me some insight on mods that I should do to this engine. One thing for sure I will be getting the cylinders bored out, and going with new pistons. It has a lot of mileage on it so that is concern number 1. Keeping the bottom end stout enough to handle anything I throw at it. My first challenge for myself and the rex is to see how fast it will run with the new bore and pistons, a cai, header, and full exhaust. I might also go throw an aftermarket cam, and cam gear in it before I run it. I was thinking about swapping the head with a the f-series vtec head as well and going with a vafc2. But I am debating with that because swapping the head might raise the compression and I love the low compression this motor has for boost. If anyone has any suggestions, wants to tell me I am crazy, or whatever you would like drop me a reply.