I've found some notes I made circa 1990 about the wind tunnels, and in particular the 8ft tunnel.
The 8ft tunnel was depressurised to a near-vaccum before accelerating: in the order of 3"Hg for supersonic acceleration, or 5"Hg for subsonic. Because at the time the evacuators (compressors really) were usually about 50% unserviceable it would take us about 30 minutes to get from 30"Hg (atmospheric) down to around 3"Hg (acceleration speed). The tunnel also used to get a lot of moisture in it so the visual cameras used to show their own condensation shock waves, separate to the supersonic shock waves we'd see on the Schlieren cameras. EFA (Typhoon) itself we only tested up to M=1.8, and my notes tell me that it was a 1:15 scale model, and to run it at M=1.8 we needed 68MW of power, and it would take 2-3 seconds to stabilise on each test condition (all run from the large soundproofed control room somewhere in the bowels of the tunnel itself.) We could position the model remotely with an accuracy of about 0.02°.
A lot of the other boffinry going on on that site was in the prediction and analysis of airframe and weapon aerodynamics, and in particular there was a lot of work going on into the interactions between weapons and the aircraft they were being dropped/fired from - the objective being (1) Not to shoot yourself down during launch, and (2) to keep the weapon intact and roughly pointing in the right direction - unsurprisingly I think that Tornado was the main direction of a lot of that research work.
We also had rather a lot of computing power at the time - I was mostly engaged with a Prime 4050 mainframe, although I think that there was a Cray-1 supercomputer around the site somewhere (or linked from our in-house computer systems anyhow) that I never got to see, but various colleagues were definitely using. Rather less power than I have on my laptop now, but it seemed very impressive then!
G