Some came with limited manufacturing head P8R which experienced 33mm ingestion valves (normally found on VTEC B-series) vs 31mm ingestion (non VTEC B series), and the head had an 84mm shrouding vs 81mm for all other B series heads. On the subject of reliability, there are only a few engines https://jdmhondab16b39544.dm-blog.com/39985893/top-guidelines-of-jdm-honda-engine