From what i remember in my 88 Prelude the engine bay was tight for a little single cam engine really not much room for anything bigger..but of course you can cut away shit and make it fit but its really not worth your money...i would sell the 89..use the money that you were gonna use on it for the H22A4 and just buy a 4th gen and go from there..IMO that is the most reasonable answer to your question.