What's the arrowed thing do? Our plenum has the machined bit to which it fits but the hole is plugged with a coreplug and the bolt holes aren't drilled.
Engine runs fine and there are no hoses or wires left unconnected so I assume it's nothing terribly important, I just think it odd that it doesn't have it when pretty much every similar engine I've seen has.
Rescued attachment RV8-EFI.jpg

Difficult to tell, but looks like it may be an Idles speed control valve, you may have an early plenum that had a seperate valve fitted..

Only a guess mind.

TT

Taken from LR manuals

HTH
James
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Idle speed controle valve then ( puts on smug grin )

TT

Don't remember that on the wiring diagrams when I wired it up. maybe it's a hot wire EFI only thing, ours is flapper

Engine in the picture is a 3.5 SD1 Vitesse engine I believe, hench why I asked.
If that is an idle control valve (the diagram is for a hotwire 3.9) then I assume our engine just does without.

Hot wire or not it should still have an idle valve of some description.

TT

You'd certainly think so but it idles fine. Or at least I think it does, it's a bit difficult to tell how lumpy it is without exhausts on and no tacho hooked up.