What Rover V8 do I have?

[rich434]

My block is marked S81D00589A. It's also marked compression ratio 9.37:1

What motor do I have?

I read that the D means cross bolted block which is a good thing!

The S81 isn't in many list of codes I've seen so far, closest is a Morgan.

I could measure the stroke through the spark plug hole if it helped...

Cheers,

Richard.

[joe_padavano]

I don't know about the "D", but the bolts on a cross-bolted block should be pretty obvious if you look at the sides of the block above the pan rail.

[MGBV8]

4.0L service engine (replacement engine)

https://www.lrfaq.org/FAQ.3.EngineDrivetrainDataTransfer.html

I believe the D is for Range Rover/Discovery

[rich434]

Turner Engineering are saying it's a 4.6 MEMES from Landrover Disco.

[MGBV8]

Maybe, maybe not.  Depending who is on the other end of the phone, the info may be about as reliable as the internet.  

It does not appear to be a regular engine that came in a Rover straight off the  production line, because that 81D engine code is not on any other Rover engine lists.

The stroke could easily be checked via the spark plug hole.  The 4.0 has a 2.8" stroke & the 4.6 is 3.2".