Some came with constrained creation head P8R which experienced 33mm ingestion valves (normally found on VTEC B-series) vs 31mm ingestion (non VTEC B series), and The pinnacle experienced an 84mm shrouding vs 81mm for all other B series heads. The B16B is like a shorter stroke equal on the B18 https://b16-honda95061.bloguetechno.com/the-ultimate-guide-to-b16-engine-76053573