Type 44 MC questions

isham-research.freeserve.co.uk at pop.pol.net.uk isham-research.freeserve.co.uk at pop.pol.net.uk
Mon Jan 15 12:01:02 EST 2001

>>One of the results of our experiments caused great debate - on an
>>ur-quattro MB engine (very close relative of the MC-1) the plate is
>>at full deflection by 4500 rpm at full boost.  So what supplies the
>>extra fuel beyond this point to redline?

> Does the MB have an O2 sensor ? A dual trace oscilloscope would be handy
> here to map plate and O2 voltages.

The O2 sensor is not useful at WOT - the mixture is deliberately set
well away from the stochiometric mean.

> So was the MB running rich at 4500 rpm or where you burning exhaust valves
> at 6000 rpm ?

CO emission measurements showed a fueling 'brick wall' on one car at
4350 rpm and full boost on a four-wheel rolling road.  This was a car
that had been 'messed with' - the volumetric efficiency had been
significantly changed without any corresponding ECU mods.

Unfortunately the rolling road was dismantled and sold before we

(As an aside, I've now answered three advertisments offering 'four
 wheel rolling road' facilities.  All have turned out to be G-meters
 rather than real facilities - ask about four-gas analysis and they're
 dead in the water.)

 Phil Payne
 Phone +44 7785 302803   Fax: +44 7785 309674

More information about the quattro mailing list