SU Electric fuel pump brief history [from SU web site and from the book “Skinner’s Union” by Mike Harvey]

1929 SU Petrolift Pump introduced

This electric pump draws petrol from the tank, which is then fed by gravity to the carburetter.
The Petrolift was phased out in 1935
Unfortunately there are no units or spares available... yet!

1931 – SU introduced a mechanical fuel pump, operated by oil pressure. However this pump was only manufactured for several years,
because of the introduction of the “L” Type

1933-34 - L Type - introduced

Low pressure 1.5 lb/sq inch. Mounted in the engine compartment usually on bulkhead, as such often referred to as a ‘puller pump’.
Two versions were made, the AUA25 single coil pump and the AUA11 dual coil pump.
The 6 volt version is part number AUA 26.
12 volt versions are AUA 25 and AUA 66.
Double ended versions of the above are AUA 11 and AUA 161.

1945-47 – HP Type introduced

The HP, high pressure [3 lb/sq inch] pump is introduced. Mainly due to rising under-bonnet temperatures and restricted space.
Available as both single and double versions, this pump was mounted on the chassis and often known as ‘pusher pumps’.
Single types were typically AUA54, AUA56. The HP pumps are now part numbers AZX 1331 and AZX 1332.
Double pumps are part numbers AUA 161 and AUA 8 (the latter being for pre-war Bentleys and Rolls Royce).

1945 - LCS Type introduced

LCS large capacity pump introduced. Typically number AUA57.
This is a high pressure, single coil pump with a large, rectangular die-cast body, mounted to the chassis and easily recognisable by this ‘square’ shaped body casting.
Part numbers today are AUA 152 and AUA 157.

1948 – L Type Body material now Mazak
The L Type pump body material changed from brass to pressure die-cast Mazak

1949 – HP Dual; Coil Type introduced

This is a dual coil, high pressure electric pump, typically AUA61, with an output of 16 gallons per hour.
This pump is designed to be mounted at the rear of the vehicle 

1959 - 200 series introduced

High pressure compact style pump. A lower capacity pump than the 300/1300 series, as fitted to Minis, Midgets and Sprites. Part number is AUF 214.

1959 - 300/400/500 Series introduced

High pressure. This pump type superseded the LCS version and can be used in place of it if necessary.
Now referred to as the 1300 series, part numbers are AZX 1307, AZX 1308, AZX 1318 and AZX 1319 although most supersede to 1307 or 1308 now.

The 400 series is the double ended version of the above.
These are now referred to as the 1400 series, part numbers are AZX 1405, AZX 1410, AZX 1408 and AZX 1416 although most now supersede to AZX 1405.

The 500 series is a double ended pump with each end working independently, mainly used as a reserve feature.
This is now referred to as the 1500 series, part numbers are AZX 1500 and AZX 1501.

N.B.

All original style points type pumps are now dual polarity and can be fitted to either a positive or negative earth. For electronic pumps see below.

All 12 volt fuel pumps are also available with electronic switching instead of the traditional points. Part numbers are the same but end in either ‘EN’ or EP’, standing for ‘electronic negative’ or ‘electronic positive’. The correct polarity must be selected to match the vehicles wiring.