I have an automatic transmission in my 91 accord. I've been repairing the 2.2 (F22A) in it for he last year and now I'm thinking it would cost me much less if I can just toss in a VTech 2.3 (F23A). It looks like it'll swap right in but I can't tell if the bolt pattern matches. Anyone have any experiance in swappint F22s out for F23s. Do I need to change the brain? Buncha questions have I.

 

Bolt pattern is the same for all F and H series engines.
You will need to run an OBDI ECM that has VTEC capability and that can communicate with your TCM, a 94/95 F22B1 EX AT ECM and harness would be the easy button.
F23A1 is similar to the F22B1 and the engine will work but ideally you would have the fueling and timing tables from the F23A1 PCM saved and then burned into a chip for the F22B1 ECM.

F23A1 PCM is not compatible with your transmission, 90-97 use the same AT, 98-02 use a different AT.