There are probably lots of T16 +4 owners on here, just ask away, someone will have an answer.
The T16 replaced the M16 engine and comes from the Rover 800 saloon , it is a reliable, naturally aspirated straightforward engine. It was mostly fitted in a plus 8 body. I have had my 93 for 4 years with no real issues.
Worth getting a Haynes manual for a Rover 800 for techie stuff. (probably available on line also) any other non engine info will be in the handbook.