In the pics you see one ALDA is bypassed and one is hooked up to the switchover valve (overboost protection). Yet both are connected to the vac line from the manifold.
I recently adjusted one of the ALDA's it was restricting fuel, yet it would go however fast I wanted to go, just getting up to speed took a while.
80 C temp is normal, as that's what the t'stat is set to.
Check all the linkage, make sure the bushings have not failed.

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looking through the photos i have of the car, it seems that both of the lines go towards the switchover valve, but at least the line that attaches on the front side of the switchover valve near the top is not connected to anything. I am thinking it may just be sitting down there under the brake master cylinder.
here are the pics if you want to see exactly what i am talking about
http://www.flickr.com/photos/38963910@N06/
the car currently does not have a thermostat in it, so there is no way unless the car just wants to run at 80 that it is actually staying there.
The linkage is the next thing to look at.
Andrew

I don't understand how it can stay at 80 C without a t'stat. Perhaps your gauge is not operating. Pull the housing and have a look, there is a rubber surround that is the gasket, reuse it.
The two pics show the switchover valve (again) bypassed, you'll see the opening at the top is not even plugged off. It's been like that since before I bought the car, six years ago.

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