I think this may be "cummingiana"
Here is a link that might be useful:
Yes that is Hoya cummingiana, what do you think of the powerful citrus rind scent?
Mike I don't mind it.
Lots of growers don't like it and say it stinks.
It took me a while to like the scent but that was because I had my plant sitting on my desk. I think this one is best enjoyed from a distance although a large plant with multiple groups of blooms would probably be hard to take, for indoor growers anyways.
Beautiful plant are you growing this Hoya outside in your garden?
Mike it is growing outside in a subtropical climate.