A bit unsure if this should be in here or in the Petrol Head Zone tbh.
Plod Triumph 2500 PI A regular sight on the M6 IIRC?
I had one of them! Not in that livery mind, but a dark green 2.5PI with overdrive. Belting car. Smooth as a baby's bum it was, though to be fair, it could usefully have used power steering - it was as good as a bullworker for building up the biceps!
And they were not as thirsty as they were reputed to be - if you understood the PI bit. It was a bit old fashioned and the fuel was metered based on manifold vacuum (who remembers the vacuum gauges sold by Halfords that everyone fitted back then?). Because of this, if the engine was off tune, this caused the manifold vacuum to drop which, in turn, caused a richer mixture, which, caused the manifold vacuum to drop which . . . You get the picture?
So, anything off in the tuning department - dodgy ignition timing, bad valve clearances, or any other tuning issue would result in massive increases in fuel consumption.
Add to this the fact that the springs in the metering unit got 'tired' and you ended up with 15 m.p.g.
However, if you were on top of tuning, and intelligently 'tweaked' the injection unit everything was good - I used to regularly get 29 or 30 out of mine. And I didn't pussy foot about in it neither!
Also had a couple of Heralds and a belting Vitesse convertible - a later one with proper suspension at the back. Soft top it was - great for pissing off MGB drivers