Some arrived with restricted generation head P8R which had 33mm ingestion valves (Usually identified on VTEC B-series) vs 31mm ingestion (non VTEC B series), and The top experienced an 84mm shrouding vs 81mm for all other B series heads. Identification: (98 spec) PR3 stamp on engine head, top rated radiator https://b16-engine89013.digitollblog.com/39732142/5-simple-techniques-for-b16-engine