What is a WX engine?

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <v04003905b0ea88401411@[10.1.1.4]> Brett Dikeman writes:

> I just made a fool of myself.

And qualified for permanent membership - we all make fools of ourselves 
from time to time.

> MB's are in '86 5000CST's maybe?

No, I don't think they're in anything but 1988/9 ur-quattros.  It _may_ be, 
though, that Audi numbered the MB/1B/MC-2 in sequence (they're basically the 
same engine) and just changed the letters.  That would roughly bring the 
numbers into sequence.
 
Don't expect to find logic such as ascending collating sequences in Audi 
codes. The MC (in its initial form) _preceded_ the MB.  It looks like Audi 
created the MAC12D (the MB's ECU) by _removing_ emission controls from the 
MAC11.
 
I'm beginning to detect some sense in all this.  It has to do, largely, with 
emission controls in Audi's markets.  The microfiche states that the WX engine 
was developed for the Swiss and Swedish markets - these were the first with 
rigorous emission controls.  Three years later, when Audi started shipping ur-
quattros to the USA, they used the Swiss/Swedish engine because the standard 
european engine (WR) could not meet US requirements.  In 1988, when the new 
engine for the 5000 was available, it was adapted for ur-quattro use in those 
countries that did not have emission controls.  Perhaps _only_ the RHD 
countries - UK, Eire, NZ, Japan, etc.?  At this point, the WX was probably 
still in production for Switzerland, Sweden and perhaps even Germany - the 
wiring diagram for the late WXs was issued six months _after_ the wiring 
diagram for the MB.

The 20V (RR in the ur-quattro, 3B in the 5000) was developed, according to the 
documentation, specifically to meet stringent emission controls.

-- 
 Phil Payne
 Committee Member, UK Audi [ur-]quattro Owners Club