Ah, a fun thread indeed . . .
The BMC 1100/1300 cars are a wonderful design, a real tribute to the creativity of both Alec Issigonis and Alex Moulton. The 1100/1300 was sold here in the US under both the MG and Austin brands. British Leyland tried hard to push the automatic in the Austin America, but it ruined performance and was very unreliable. The cars were conceptually light years better than the best-selling import, the VW Beetle, with superior ride, handling, and space utilization, but the Beetle was pretty much unbreakable while BL products didn’t hold up well at all. BL knew they had a problem here in the US, but their fix was to replace the America with an equally poorly made Marina that had none of the engineering virtues of the 1100/1300. It's funny how things have now changed: VWs now usually feature advanced engineering, but reliability isn't one of their modern virtues (don't ask how I know this!)
The whole BMC 1100/1300 lineup with the transaxle in the sump was based on the technology of the original Mini. Lamborghini engineers were fascinated by these cars too, enough to crib the layout for their stunning ’67 Muira. In their case, however, they used a transverse V-12 behind the driver with a sump-mounted five speed transaxle. Using the same oil for the engine and gearbox was problematic for the Muira as well, with Lamborghini eventually separating the oil supply to each component. I've often wondered if there's any record of what Issigonis thought of the Muira and Lambo's interpretation of his layout on such a vastly different scale.
I love most all old cars, but have a special thing for classic Citroens. My own dream car is my ’73 SM. At the moment it’s off the road until I do some major maintenance – it’s time for new timing chains, and the sodium cooled OEM valves should be checked – but it’s now 36 years old (built in May ’73) so a few worries are to be expected. I also have a ’71 DS21, but doubt that I’ll ever have the time to restore it. That’s sad as I grew up with D series cars and they’re a wonderful combination of supreme comfort with serious toughness. My DS has over 200,000 miles on it, while the SM is comparatively youthful with only 71,000.
The SM has one thing in common with the Imperial and Austin Allegro: the steering wheel isn’t round. In the case of the SM, it’s elliptical to match the elliptical instruments. Since the steering is very, very quick you never feel the unusual shape as it only goes one turn to the left and one to the right. It also has a powered return to the center position, and firms up according to the speed of the car. The steering speed governor circuit runs off the nose of the transaxle and is also tapped to control the cooling fans: at 30 mph they turn off since airflow through the grille renders them unnecessary.
Here’s a pic of an SM dash which shows both the steering wheel and instruments. This isn’t mine but the interior is the same, aside from this one having the very elegant Continental Edison radio never offered in the US.
