The reason most H23A/H22A combinations don't work that well is people don't realize there is a lot more to an LS/VTEC than just a VTEC head. I'm not really familiar with H22/H23's, but I know with an LS vs a GS-R, there is a higher flow oil pump, differently geared water pump, oil squirters and a block girdle (among others) to strengthen the engine in a B18C1 that a B18B doesn't have. If you put a B18C head on a B18B block without upgrading the rest, your going to find out why everybody says LS/VTEC's aren't reliable. Most likely there are similar modifictions that are nessicary to make an H23/VTEC run reliable for a long time. Seeya.