Re: 1500S Engine ??

[Aaron Britcher <abritcher@ezinet.com.au>]

Mel and Jim,
	The 'S' engine! The most powerful Type 1 based derivative from 
the VW factory! 66bhp versus 1600 dual port, dual carb 65bhp. Anyways, 
here are the details that I can remember which diferentiate this from 
the single carb engine of the same years.
First off the engine is not numbered anything differently to the 
standard single carb 'N' models produced at the same time so you can not 
assume anything from the engine number unless you have proof of that 
number from VW records and such. My engine is numberred 0 682 209 so 
there you go. Displacement is still 69mm x 83mm for 1493cc's however the 
first year of production to all countries had domed 83mm pistons which 
gave a higher compression ratio, 8.5:1 rather than 7.7:1 (from memory). 
After August 1964 (65 model year) VW used flat crown 83mm pistons for 
export markets due to the unfavourably crappy fuel octane in other parts 
of the world. As far as my friends in Germany can tell they got domed 
83mm pistons until the end of production ('S' model ran from August 1963 
to August 1965- not a common model!). All 'S' engines were equiped with 
a pair of solex 32PDSIT's except those with the M option of single carb 
(obviously), but why would you order an 'S' without dual carbs? Strange 
that some people did! Also the distributor was different to single carb 
in that it was a ZVJCU4R3 which is a combined mech and vac advance 
distributor. During August 1964 VW changed that to a 311 905 205D (still 
'S' only) which was vac only and better matched to the carbs which were 
also modified at the same time (different jets and venturi sizes- I have 
details if you want me to dig them up). The fual pump was the same, coil 
etc, exhaust was almost the same and had either a blank over the heat 
riser pipe or no heat riser pipe at all. Also the right hand side heater 
had a blank bolted to where the heat riser would be for a single carb 
engine as you no longer needed the heat riser tube. The oil relief valve 
within the engine was also different on the 'S' and had a groove around 
the top of it as opposed to the single carb which had a standard 40hp 
relief valve. Heads were identical, cam, crank etc. There are a few odds 
and sods that are next to impossible to get now like the dual carb fuel 
'T' which as far as I know is 'S' only. The breather tower is slightly 
different from the 'S' to the 'N' but nothing to worry about (will look 
up details if you want). 'S' models also had the chrome tip on the 
exhaust as standard on the T34 (not easy to get NOS now!). No doubt I 
have probably forgotten a few things but now that my 'S' engine is back 
together after a six or so month rebuild I'm not interested in the 
details as much- it's finished and it runs choice! I have a lot of 
literature on the 'S' models from Germany and the factory workshop 
manuals so I probably have enough resources to give you the entire story 
on the 'S' but only if you ask (too much to write now). Also the 'S' was 
more than just some wheel trims and different engine, the entire 
interior changed slightly over production and parts for the interior are 
now non-existant. My personal view is that the 'S' was the best Type 3 
version ever produced, particularly the Notch.

Aaron.