Interesting link on Engine Codes...

[Aleksander Mierzwa]

At 10:56 00-11-22, quk at isham-research.freeserve.co.uk wrote:

>> They did not. KG engine does not have any emissions control systems and is
>> designed to operate on 98 RON leaded fuel. Hence the higher output. Because
>> all cars sold in the USA are required to operate on 87 AKI (roughly 92 RON)
>> unleaded fuel, the compression ratio of the KG was lowered, emissions stuff
>> was added and that's how the KH engine found on 84-85 5KTs was born.
>
>I think this picture is a little confused.
>
>The KG engine was used in European 200s up to February 1988.  The KH is
>a low-emission form destined for the Japanese market - I don't know
>whether it was also sold in environmentally-sensitive countries like
>Sweden and Switzerland, but we don't have any in the UK.  From February
>1988 to December 1990 the 200 used the 1B engine - this is a derivative
>of the MC-1 and virtually identical to the MB used in the ur-quattro
>during the 1988 and 1989 model years.  Nominally 200 bhp. The 200
>was dropped from the programme in model year 1991 (actually November
>1990) to protect the new V8.  Since there wasn't a V8 Avant, Audi
>produced a limited number of 100TQWs to 200 specifications apart from
>seats and bodywork, and these were fitted with 165bhp MC-2 engines.

UK was slow to introduce strict emissions standards. That's why you are
more familiar with engines like KG, MB and 1B, Phil. They all don't have
any emissions control stuff and are designed to operate on 98 leaded fuel.
Over here most cars are German imports. Germany introduced stricter
emissions regulations around 1985, I believe, so most German market late
model 200s have the MC (let our German listers correct me if I'm wrong). I
once test drove (and was close to buying) an '88 200q (German import) and
it had same MC-1 engine as my '87 5KT (at least no visual differences were
apparent). You are right that KG was produced up to Feb 1988. Those cars
were designed for export to countries which still allowed leaded fuel, non
emissions controlled cars. Same applies to 1B. I don't have any production
figures, but I doubt 1B was produced in significant numbers, though. By
this time most countries already had introduced stricter emissions standards.
A side note to our American listers: the reason why early US-spec Audis are
detuned in comparision to their European counterparts is because USA was
first to introduce strict emissions regulations, banning leaded fuel and
requiring all cars to have cats, 02 sensors AND to be able to run on 92 RON
fuel. Before the introduction of knock sensors the only way to achieve this
was to lower the compression and retard the timing. That's why KH has only
140-something hp vs 174 of the KG, which will run on nothing but 98 leaded
fuel though. So all suggestions I occasionally hear that "Audi detunes the
cars because they believe Americans can't drive" etc. are hogwash. Later
engines: MC, NF, 3B etc. all have exact or very similar hp ratings as their
European versions.
--
Aleksander Mierzwa
Warsaw, Poland
87 5KT