Exploring an SU carburettor

Carburettors seem to be a 'thing of the past', so that cars can conform with Californian laws on emissions, but for many decades, they allowed the average mechanic to adjust engines to run very efficiently.
All they do is mix fuel with air, metering the mixture to get the best 'burn', and controlling the amount of the mixture that goes into the cylinders.
The SU types of carburettors are to be found on Minis, Morris Minors and many classic British cars. No surprise then to find one on an Austin Nautilus, although I think this one is much younger than the engine.

[@0Fosgate0]

Just what i was looking for: a concise explanation. Thank you.

[@harryfaber]

+0Fosgate0 Glad you found it of use.

[@zx8401ztv]

Yes i mix up the choke and enrichment system, my frends motorbike uses an automatic choke...sorry enrichment system, im still stuck in the past when i was 17 and riding around on a puch maxi moped, it had a slideplate choke.
Good days :-)

[@thornwarbler]

That was an excellent explanation ..............................Cheers

[@harryfaber]

+thornwarbler Thank you for coming along. I suppose I ought to pull that engine out from under the bench again.

[@thornwarbler]

That would be good.

[@harryfaber]

Never had one of those, although I did have an Ariel 3.