Some arrived with constrained production head P8R which had 33mm intake valves (Typically observed on VTEC B-series) vs 31mm intake (non VTEC B series), and the head had an 84mm shrouding vs 81mm for all other B series heads. The Honda B16 engine has cemented alone within the JDM aftermarket https://raymondpmhdx.blog-a-story.com/21367260/the-smart-trick-of-b16b-that-no-one-is-discussing